Literature Number: DS-SY1007 January 31, 2014 Rev. 1.4 SY1007 GNSS RF Front-End DATASHEET www.saphyrion.ch DATASHEET SY1007 GNSS RF Front-End Document Team Author Francesco Piazza Reviewers Lorenzo Moriggia Christian Iera Mariano Perna Angelo Consoli Revision History Rev. 1.0 1.1 1.2 1.3 1.4 Date September 16, 2009 November 26, 2009 October 4, 2011 August 19, 2013 January 31, 2014 Who fp fp fp fp fp Description SPH document created, loosely derived from previous versions. Expanded all sections (based on customer support requests). Corrected errors and typos, added new sections (10 to 15). Extended Sections 4, 5, 7 and 13, corrected typos (all sections), added application example (Section 16). Re-characterization of the VCOs: updated VCOs tuning curves and phase noise specs, added VCOs phase noise graph. Added handling precautions (Section 14), corrected IF PLL range. Contents 1 General Description 1 2 Features 1 3 Applications 1 4 Absolute Maximum Ratings 2 5 Electrical Characteristics 2 6 Device Marking 4 7 Typical Operating Characteristics 5 8 Pin Description 6 9 Equivalent Circuits 7 10 Circuit Description 9 11 Serial Interface 10 12 Register File 11 13 Applications Information 12 14 Handling Precautions 17 15 Radiation Tolerance 17 16 Application Example 18 17 Layout Recommendations 21 18 PCB Recommendations 21 19 Mounting Recommendations 22 20 Package Drawing 23 ii Saphyrion Sagl Rev. 1.4, January 31, 2014 SY1007 GNSS RF Front-End DS-SY1007 Rev. 1.4 - January 31, 2014 DATASHEET 2 Features 1 General Description The SY1007 is a programmable dual conversion superheterodyne receiver. Both the RF and the IF local oscillators can be independently programmed to accommodate various frequency plans. It can be configured to receive all GPS, all GLONASS and most Galileo signals in the L-band up to a bandwidth of 24MHz by selecting the appropriate external components and configuring the RF and IF PLLs. The output is analog quadrature (I/Q) at base-band. Four low latency power down modes are provided to aid in implementing different power saving schemes. Complete, highly integrated RF front-end. Supports all GNSS signals up to 24MHz bandwidth. Compact, low bill-of-materials, small PCB area. Low voltage operation, low power consumption. • The SY1007 is a radiation hardened L-band RF downconverter for GNSS receivers aimed at the professional and space markets. This device is designed in a 0.35µm SiGe process and includes all functional blocks needed to implement the complete RF front-end of multiband GNSS receivers, thus allowing a substantial reduction of BOM, size and weight with respect to discrete designs. It directly interfaces to the ESA AGGA-4 GNSS base-band processor. • • – – – – – AVDD: 2.4V to 3.6V, DVDD: 2.2V to 3.6V. Fully active: 12.3mA Stand-by: 3.3mA Doze: 280µA Sleep: < 1µA Supports passive and active antennas. Flexible 2MHz to 5MHz reference frequency. Analog quadrature I/Q outputs. Compact 6mm x 6mm ceramic-metal BGA package. • • • • 3 Applications Since the SY1007 mainly targets the space market, a variant qualified to ESA ESCC9000 for satellite applications is available. This variant has demonstrated latch-up and radiation damage free operation. The SY1007 comes into a compact 6mm x 6mm ceramic-metal hermetic BGA package containing no organic materials. Space-borne GNSS receivers. Precise orbit determination. Antenna arrays, beam forming, attitude determination. Multi-frequency precision/monitoring GNSS receivers. Reliable GNSS receivers, safety of life. • • • • • Figure 1: SY1007 Block Diagram. C4 A5 B4 A4 IF2P B5 IF1P RFP C3 MIXN A6 MIXP C5 RFN LNO B6 C5 SAW or LC SAW D6 AVDD DVDD IF-Filter 2 L4 C6 B3 E6 AVDD B1 DVDD DBM I LNA RFin C1 DBM IF-Amp VGA L2 LPF (15MHz) LNI F6 DBM L1 F2 :N1 D1 D2 Buffers Q :4 OIP OIN log OQP C1 OQN C2 AGCI A3 RCP A1 VB bias E5 I :2 Q :2 :N2 VBG C8 C3 C4 C6 D3 D4 F5 RL1 D5 RL2 F3 L5 RF LO inductor F4 IF VCO PFC RPLL AVSS RENB RF VCO SY1007R E3 R1 C9 IENB C7 E4 C10 RF Loop filter PFC To ADC, base-band processor IF-Filter 1 C2 IF2N RF-Filter L3 IF1N GNSS Antenna A2 reg DIO IL1 IL2 E1 L6 IF LO inductor F1 IPLL DVSS E2 R2 C11 B2 C12 IF Loop filter c 2014 Saphyrion SAGL. All Rights Reserved. All trademarks and registered trademarks are the property of their respective Copyright owners. Saphyrion SAGL reserves the right to change the detail specifications as may be required to permit improvements in the design of its products. Saphyrion SAGL assumes no responsibility for this product’s use, nor for any infringement of patents or other rights from third parties which may result from its use. No license is implied under any patent or patent right by Saphyrion SAGL. Saphyrion SAGL, CH-6934 Bioggio, Switzerland, http://www.saphyrion.ch 1 DATASHEET SY1007 GNSS RF Front-End 4 Absolute Maximum Ratings Max. supply voltage, AVDD, DVDD . . . . . . . . . . . . . . . . . . . . . . . . . 4.0V Max. RF input on LNI, RFx . . . . . . . . . . . . . . . . . . . . . . . . . . . . +10dBm ESD susceptibility, HBM, JESD22-A114 . . . . . . . . . . Class 1B, 1KV Continuous power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . 300mW Current on any pin except LNI, RFx . . . . . . . . . . . . . . . . . . . . . . ±1mA Current on supply and VB pins . . . . . . . . . . . . . . . . . . . . . . . . . .±50mA Current on VBG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±10mA Operating junction temperature . . . . . . . . . . . . . . . . . −55 to +125◦ C Storage temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65 to +150◦ C Lead temperature (soldering, 40s) . . . . . . . . . . . . . . . . . . . . . . . . 240◦ C Voltage on any pin except LNI, RFx . . . . . . . . . . −0.3V / xVDD+0.3 Voltage on LNI (note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±0.3V Voltage on RFx (note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +1.5V Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. Absolute maximum ratings are short term stress ratings only; functional operation of the device at these or any other conditions beyond those indicated in the recommended operating conditions is not implied. Exposure to absolute maximum ratings conditions for extended periods may affect device reliability. ESD sensitive device: Use proper precautions when handling this device. Pb Device contains lead: Product is not RoHS compliant and shall be handled accordingly. Do not disperse into the environment. 5 Electrical Characteristics AVDD = 2.4V to 3.6V, DVDD = 2.2V to AVDD+0.2V, f(RCP) = 2.0MHz, Tjunction = −40◦ C to +125◦ C, no load, unless otherwise stated. All voltages are referred to their respective VSS. Typical values are at AVDD = 3.0V, DVDD = 3.0V, Tjunction = +25◦ C. Parameter Conditions Min Typ Max Unit Notes 1575MHz, noise matched 1575MHz, Z-matched 1575MHz, noise matched 1575MHz, Z-matched Input referred Noise matched IP3, Input referred S11, noise matched S11, Z-matched S22 18.2 18.9 20 1.6 4.5 −23 1.25 −10 −2 −15 −12 25.0 dB dB dB dB dBm ns dBm dB dB dB 2 2 2 2 2 2 2 2 2 2 15 26 11.0 −13 −3 16 29 13.5 dB dB dB dBm dBm dB Ω Ω kΩ pF 3 3 dB dB mV/dB V mV Vpp MHz MHz Ω pF 5 5 5 LNA Power gain Noise figure 1dB compression point Group delay Third order intercept Input refl. coefficient Output refl. coefficient −24 1.19 −14 1.8 −20 1.29 RF Mixer and 1st IF Stage Conversion voltage gain SSB noise figure 1dB compression point Third order intercept Input refl. coefficient Differential resistances Diff. capacitance To MIXP-MIXN, no load To IF1P-IF1N, no load Differential output Input referred, to MIXP-MIXN Input referred, to MIXP-MIXN S11 at 1.5742 GHz MIXP to MIXN IF1P to IF1N IF2P to IF2N MIX, IF1 and IF2 14 24 −16 500 500 54 600 600 65 0.5 64 50 6 1.5 −30 1.4 10 12 120 66 80 9 1.8 −15 720 720 81 3 3 4 4 4 IF Amplifier and Base-Band Section VCA voltage gain VCA gain control range VCA sensitivity DC output voltage DC offset voltage Output signal amplitude IF amp bandwidth I/Q 3dB Bandwidth I/Q output Impedance I/Q load capacitance 2 I/Q output, V(AGCI) ≥ 2V V(AGCI) = 0.3V to 2V, Fig. 8 pin AGCI I/Q to AVSS, VDD=2.5V I/Q outputs ≤ 1dB compression Internal low-pass filter See note 6! No bandwidth reduction Saphyrion Sagl 12 2.1 +30 1.8 15 125 400 18 150 10 6 Rev. 1.4, January 31, 2014 DATASHEET Parameter SY1007 GNSS RF Front-End Conditions Min Typ Max Unit Notes 1.50 1050 255 63 GHz MHz/V 14 14 Local Oscillator, RF PLL VCO frequency range VCO sensitivity Main PLL divider range Charge Pump Current PLL SSB phase noise PLL spurs Ext. RF LO amplitude Ext. RF LO resistance Ext. RF LO capacitance L=4.7nH between RL1 & RL2 L=4.7nH between RL1 & RL2 Pin RPLL 100Hz offset 1kHz offset 10kHz offset 100kHz offset 1MHz offset Recommended loop filter Between RL1 & RL2, RENB=1 Between RL1 & RL2, RENB=1 Between RL1 & RL2, RENB=1 1.35 740 64 42 880 50 −58 −66 −68 −70 −100 −40 +5 −17 10 1.5 µA dBc/Hz dBc/Hz dBc/Hz dBc/Hz dBc/Hz dBc dBu kΩ pF 7,14 7,14 7,14 7,14 7,14 15 Local Oscillator, IF PLL VCO frequency range VCO sensitivity Main PLL divider range Charge Pump Current PLL SSB phase noise PLL spurs Ext. IF VCO amplitude Ext. IF VCO resistance Ext. IF VCO capacitance L=47nH between IL1 & IL2 L=47nH between IL1 & IL2 Pin IPLL 100Hz offset 1kHz offset 10kHz offset 100kHz offset 1MHz offset Recommended loop filter Between IL1 & IL2, IENB=1 Between IL1 & IL2, IENB=1 Between IL1 & IL2, IENB=1 360 160 32 42 250 50 −78 −86 −88 −95 −110 −60 420 298 255 63 +5 −17 10 2.0 MHz MHz/V µA dBc/Hz dBc/Hz dBc/Hz dBc/Hz dBc/Hz dBc dBu kΩ pF 16,17 16,17 7,16 7,16 7,16 7,16 7,16 7 15,17 Voltage Regulator Band-gap voltage Band-gap output current Band-gap load regulation Regulator output voltage Regulator line regulation Regulator output current Regulator load regulation No load 1.12 200 I(VGB) = 0 to −200µA No load AVDD 2.4V to 3.6V 1.8 1.17 1.22 2 1.9 4 5 2.0 10 7 15 1 I(VB) = 0 to −4mA V µA mV V mV mA mV 8 8 9 Digital Interface Reference Freq. Range Input capacitance Input high level Input low level Output high level Output low level Output rise time Output fall time 1.9 RCP and DIO 5 1.0 0.7 DVDD −0.2 0.9 DVDD I(OH) = −1mA I(OL) = +1mA C(LOAD) = 5pF C(LOAD) = 5pF 3.4 2.8 MHz pF DVDD+0.2 V 0.3 DVDD V V 0.1 DVDD V 6.1 ns 4.8 ns 10 10 Power Supply Supply Voltage Supply Current Analog Digital Fully active Stand-by Doze Sleep Rev. 1.4, January 31, 2014 AVDD DVDD AVDD DVDD AVDD DVDD AVDD DVDD AVDD/DVDD 2.4 2.2 9.5 20 2.0 20 180 2 Saphyrion Sagl 12.5 40 3.3 40 280 5 3.6 AVDD+0.2 19.0 80 5.5 80 380 10 100 V V mA µA mA µA µA µA nA 11 11 11 11 3 DATASHEET SY1007 GNSS RF Front-End Parameter Conditions Min Typ Max Unit +125 +125 ◦ Notes Thermal Characteristics Operating temp. range Guaranteed performance No degradation Junction to case Thermal resistance Rth −40 −55 25 C C ◦ C/W ◦ Radiation Characteristics Total dose (C60) Dose rate (C60) LET 100 12 No latch-up 45 kRad(Si) Rad/min 2 MeV cm mg 18 Notes Note 1: LNI and RFx pins shall be AC coupled. Setting LNI to 0V disables the LNA. Shorting RFx to VSS will damage the device. Note 2: LNA with recommended input and output matching networks (see section 13.3.1). Note 3: Voltage conversion gain, differential, input is RFP-RFN, output as indicated, unloaded. Note 4: I/O impedances track to 5% or better. Note 5: Voltage gain, from IF2P-IF2N, differential, to OIP-OIN or OQP-OQN, also differential. Note 6: Caution: OIP-OIN and OQP-OQN shall not be loaded with less than 10kΩ, or severe distortion and amplitude limiting will occur. Note 7: Closed PLL loop, with 33µF decoupling capacitors on VBG pins to reduce noise of bias circuit. Note 8: Minimum current available to an external load under worst-case conditions. Note 9: Doze mode, internal loads are turned off. Note 10: Measured between the 10% and 90% points. Load capacitance on these pins must be minimized (preferably below 5pF). Note 11: Supply current increases with temperature (see Figure 12). Note 12: Minimum and maximum frequency allowed. Note 13: Voltage range needed to guarantee full AGC regulation. Note 14: With L = 4.7nH, muRata LQW18, reference test board. Other frequency ranges may be obtained using different inductor values. Note 15: Referred to 50Ω (0dBu=223.6mV). Signal levels between −8dBu and 0dBu give the best, most stable performances. Note 16: With L = 47nH, muRata LQW18, reference test board. Other frequency ranges may be obtained using different inductor values. Note 17: IF local oscillator frequency is half the VCO frequency, i.e. f(LO) = f(VCO)/2 (see Section 10). Note 18: DUTs have been tested at 85◦ C and xVDD=3.6V until a cumulated fluence of 1E+7 ions/cm2 without detecting any latch-up. 6 Device Marking The marking of the device is in accordance with the requirements of ESCC Basic Specification No. 21700. The information to be marked on the component shall as a minimum be: • • • Terminal identification. Component number. Traceability information. Engineering model marking may occasionally deviate from the specification shown here. Please consult with Saphyrion in case of doubt. SY1007R – Engineering Model (EM) Marking 07 YYWW Rxxx A1 dot and die part number: 07=SY1007. YYWW = Year and week of sealing. R = EM part, xxx = Unique serial number. SY1007S – Flight Model (FM) Marking 07 YYWW Sxxx 4 A1 dot and die part number: 07=SY1007. YYWW = Year and week of sealing. S = FM part, xxx = Unique serial number. Saphyrion Sagl Rev. 1.4, January 31, 2014 DATASHEET SY1007 GNSS RF Front-End 7 Typical Operating Characteristics Figure 3: LNA Linearity +20 15 0 LNA noise matched at 1.57GHz 10 NF (dB) 5 Figure 4: LNA S11 and S22 +10 +5 CP 0 S11-S22 (dB) 20 Pout (dBm) Gain (dB) Figure 2: LNA Gain and NF. IP3 -20 -40 2 -5 -10 -15 -30 -60 1.5 -25 1 1.0 1.2 1.4 1.6 1.8 Frequency (GHz) -80 -50 2.0 Figure 5: RF Mixer Gain -40 -30 -20 Pin (dBm) -10 0 Figure 6: RF Mixer Linearity 30 S11 S22 -30 1.0 1.2 1.4 1.6 1.8 Frequency [GHz] 2.0 Figure 7: LNA S21 and S12 +30 +30 +20 +10 To MIXP-MIXN CP +10 -10 S21-S12 (dB) 20 Vout (dBu) Voltage Gain (dB) To IF1P-IF1N IP3 -30 10 0.0 -10 -20 -30 -50 -40 0 -60 -30 0 30 60 90 Temperature (°C) -70 -40 120 Figure 8: IF Amp Gain vs. AGC -30 -20 -10 Pin (dBm) 0 -50 1.0 +10 Figure 9: RF VCO tuning curve L(IF) = 47nH -40°C 0 -55°C 3.6V 1.55 3.6V 1.50 3.0V 2.4V 1.45 1.40 1.35 -40°C 25°C 125°C -30 1.30 -60 0 1 2 AGC Voltage (V) 3 Figure 11: VCOs phase noise 1.25 0.0 -80 IF-LO -100 2.4V 200 IF LO frequency is shown (VCO is at 2x LO frequency). 190 180 -40°C 25°C 125°C 160 0.0 2.5 0.5 1.0 1.5 2.0 Tuning Voltage (V) 2.5 Figure 13: VBG/VB vs. Temp. 1.914 VB 16 RF-LO -60 1.0 1.5 2.0 Tuning Voltage (V) 18 f(RF-LO) = 1400MHz f(IF-LO) = 185MHz f(RCP) = 2.0MHz -40 0.5 3.0V 210 170 Figure 12: I(AVDD) vs. Temp. 14 I AVDD (mA) Phase noise (dBc/Hz) -20 Frequency (MHz) 27°C 2.0 220 3.6V 2.4V 12 10 Output Voltage (V) 125°C 30 Frequency (GHz) Gain (dB) 85°C 1.4 1.6 1.8 Frequency [GHz] 230 L(RF) = 4.7nH 1.60 60 1.2 Figure 10: IF VCO tuning curve 1.65 90 S21 S12 1.910 1.184 VBG 8 1.181 -120 1 10 100 1k 10k 100k 1M Frequency offset (Hz) Rev. 1.4, January 31, 2014 6 -60 -30 0 30 60 90 120 Temperature (°C) Saphyrion Sagl -40 -20 0 20 40 60 Temperature (°C) 80 5 DATASHEET SY1007 GNSS RF Front-End 8 Pin Description 1 2 3 4 5 6 A B C D E F Figure 14: SY1007 pin-out (top view). Name RCP DIO AGCI IF2P IF1P MIXP DVDD DVSS IF2N IF1N MIXN RFP OQP OQN AVSS AVSS RFN AVSS OIP OIN AVSS AVSS RENB LNO IL1 IPLL RPLL IENB VBG AVDD IL2 VB RL1 RL2 AVSS LNI 6 Ball A1 A2 A3 A4 A5 A6 B1 B2 B3 B4 B5 B6 C1 C2 C3 C4 C5 C6 D1 D2 D3 D4 D5 D6 E1 E2 E3 E4 E5 E6 F1 F2 F3 F4 F5 F6 Domain DVDD DVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD AVDD Description External reference clock. Digital input output interface, needs a weak pull down. Test: scan output. Set the AGC IF conversion gain, to be connected to a decoupling capacitor. IF VGA positive input. First IF amplifier positive output. RF mixer IF positive output. Positive digital supply voltage. Negative digital supply voltage. IF VGA negative input. First IF amplifier negative output. RF mixer IF negative output. Radio frequency positive mixer input. Quadrature base-band GNSS positive signal. Quadrature base-band GNSS negative signal. Negative analog supply voltage. Negative analog supply voltage. Radio frequency negative mixer input. Negative analog supply voltage. In-phase base-band GNSS positive signal. In-phase base-band GNSS negative signal. Negative analog supply voltage. Negative analog supply voltage. RF PLL enable – active low. Test: scan enable (SE). LNA output. IF VCO tank-circuit – first terminal. IF PLL loop filter. Output of the PLL phase frequency comparator, connect to the output filter. IF PLL enable – active low. Test: scan input (SI). Band-gap voltage reference output, 1.2V. Decouple to AVSS close to the chip. Positive analog supply voltage. IF VCO tank-circuit – second terminal. Voltage regulator output, 1.9V. Decouple to AVSS close to the chip. RF VCO tank-circuit – first terminal. RF VCO tank-circuit – second terminal. Negative analog supply voltage. LNA input. Saphyrion Sagl Rev. 1.4, January 31, 2014 DATASHEET SY1007 GNSS RF Front-End 9 Equivalent Circuits Pin A1 A2 D5 E4 Description RCP DIO RENB IENB Equivalent circuit Digital inputs and outputs xVDD RENB, IENB, RCP, DIO ESD ESD ESD ESD xVSS E3 E2 RPLL IPLL DVDD DIO DVSS PLL charge pump outputs AVDD 50µA UP RPLL IPLL DN ESD CLAMP 50µA AVSS F6 D6 LNI LNO LNA input and output AVDD 500 ESD LNO bias-1 bias-2 18k LNI ESD ESD AVSS B6 C5 RFP RFN RF mixer input (internally matched to 50Ω) AVDD ESD ESD Bias RFP RFN ESD ESD AVSS A6 B5 A5 B4 MIXP MIXN IF1P IF1N IF input/output AVDD 300Ω MIXP, IF1P 300Ω ESD ESD MIXN, IF1N Mixer IF-amp ESD ESD AVSS Rev. 1.4, January 31, 2014 Saphyrion Sagl 7 DATASHEET Pin A4 B3 SY1007 GNSS RF Front-End Description IF2P IF2N Equivalent circuit IF VCA input (AGC) AVDD VBG ESD 65kΩ 65kΩ ESD IF2P IF2N ESD ESD ESD ESD AVSS A3 AGC AGC control circuit, gain control input AVDD ESD AGCI ESD AVSS C1 C2 D1 D2 OQP OQN OIP OIN Quadrature I/Q base-band outputs AVDD ESD OIP OQP OIN OQN ESD AVSS F3 F4 E1 F1 RL1 RL2 IL1 IL2 RF and IF voltage controlled oscillators AVDD RL1 IL1 RPLL IPLL 8 Saphyrion Sagl ESD ESD ESD ESD RL2 IL2 AVSS Rev. 1.4, January 31, 2014 DATASHEET 10 SY1007 GNSS RF Front-End Circuit Description The SY1007 is a radiation hardened super-heterodyne RF front-end for GNSS receivers aimed at aerospace applications. It offers a high degree of versatility and can be configured to receive all GPS, all GLONASS and most Galileo signals in the L-band up to a bandwidth of 24MHz by selecting the appropriate external components and configuring the RF and IF PLLs. The output is base-band analog I/Q. All active building blocks needed to construct a GNSS RF receiver channel are included on-chip. RF and IF filters are external to the chip such that their bandwidth and order can be selected to suit the needs of various applications. 10.1 LNA The LNA is a single stage cascode amplifier. It requires external matching networks at both its input and output and can be configured for all GNSS frequencies by adjusting the matching networks. It provides about 20dB gain and 1.6dB NF under noise matching conditions. Pin LNI is the LNA input, is biased to about 0.7V and shall be AC coupled. Pin LNO is the output of the LNA and needs to be biased at AVDD. If desired the LNA can be disabled permanently by connecting its input to AVSS. In that case an external LNA is needed. as a vectorial I/Q signal on pins OIP, OIN, OQP and OQN. In order to obtain an accurate I/Q output the quadrature LO signal is obtained with a divider-by-2. In consequence, the IF-VCO frequency shall always be set to 2x the required LO frequency to compensate this division. The VCO signal can be generated either by the on-chip IF-VCO or can be supplied by an external PLL to pins IL1 and IL2 as a differential signal. Pin IENB selects between internal PLL (IENB = 0) and external LO signal (IENB = 1). 10.5 RF and IF PLLs The SY1007 requires 2 local oscillator signals: one for the RF and a second one for the IF downconverters. These signals can be either generated by the on-chip RF and IF local oscillators or supplied externally. The VCOs are balanced LC oscillators and require one external coil. (Register) N Loop Filter RF Mixer VCO RCP LO (Register) N (4-255) :2 :2 Loop Filter 2xLO I/Q Mixers VCO 10.2 RF Mixer RCP The RF mixer converts the RF signal to the 1st IF. The mixer is double-balanced, provides a voltage gain of 15dB and a SSB noise figure of 11dB. The input is balanced and provides a broad-band 50Ω impedance to directly match typical SAW filters for GNSS use. The output of the mixer is balanced, has an impedance of 600Ω and is meant to be connected to an LC tank-circuit (part of the IF filter). It is directly connected to the 1st IF amplifier stage internally. The local oscillator signal is either generated by the on-chip RF-VCO or can be supplied externally to the pins RL1 and RL2 as a differential signal. 10.3 IF-Strip The IF-strip consists of a fixed gain (11dB) amplifier followed by a 3-stage variable gain IF amplifier with logarithmic (dB-linear) gain control. A differential amplifier structure has been used to achieve rejection to common mode signals. The input of the fixed gain stage is connected to the mixer, while the 600Ω output is available on pins IF1P and IF1N, which are meant to be connected to the 2nd section of the LC IF-filter. The variable gain amplifier provides about 45dB gain and ≥ 50dB control range. The input is balanced, has an impedance of about 65kΩ and is biased at 1.2V by the band-gap voltage reference. The output is internally connected to the following stages and is not accessible externally. 10.4 I/Q Downconverter The I/Q downconverter converts the output of the IF-strip to a base-band signal. This quadrature downconverted signal is then low-pass filtered by a 3rd order Bessel active filter with 15MHz bandwidth, amplified by 12dB and output Rev. 1.4, January 31, 2014 :4 (64-255) Figure 15: SY1007’s RF and I/Q PLL configuration. The integer-N PLLs are independent from each other and can be programmed via the serial interface. They both use the clock signal applied to pin RCP as reference. Their output frequency is calculated as follows (see figure 15): • RF PLL: f(RF-LO) = 4*N1*f(RCP); 64≤N1≤255. • IF PLL: f(IF-LO) = N2*f(RCP) ⇒ f(IF-VCO) = 2*N2*f(RCP); 32≤N2≤255. The CRC loop filters shall be connected to pins RPLL and IPLL respectively. The RF and IF PLLs can be enabled independently by setting pins RENB and IENB to logic low. When disabled (pins xENB to logic high) the balanced external local oscillator signals shall be applied to pins RL1RL2 and IL1-IL2 respectively while pins RPLL and IPLL shall be left open. The PLL enable pins RENB and IENB are also used as test inputs by the testability logic. 10.6 Band-Gap Reference It is a band-gap voltage reference generating approximately 1.17V. It is used by most analog blocks and its output is available on pin VBG. It is able to source up to 200µA but can sink a couple µA at most. It requires an external capacitor ≥1µF for stability, although larger capacitors are recommended to reduce noise voltage. 10.7 LDO Voltage Regulator It is a linear low drop-out voltage regulator meant to generate the supply voltage for the parts of the SY1007 that are sensitive to power supply noise and ripple (mainly the Saphyrion Sagl 9 DATASHEET SY1007 GNSS RF Front-End PLL). The nominal output voltage is 1.9V. A ≥1µF capacitor – which can be increased without limit – is required for stability. The LDO is able to source up to 15mA and its output is the VB pin. Although not explicitely meant to supply external loads, the LDO can power external circuits consuming up to 1mA, provided that they don’t generate power supply noise that would disturb the internal SY1007 sensitive parts. aborted. The second 8-bit block contains the data read or written to the selected register, in LSB-first form. Back-to-back communications (no idle cycles between two consecutive communications) are supported. If DIO is pulled high immediately after the completion of the previous communication, the SY1007 accepts a new communication already at the clock cycle following the last data bit (bit D7). 10.8 Serial Bus and Register File 11.2 Timing Diagram A configuration register, accessible via a single-wire serial interface, is implemented on the SY1007. Its purpose is to configure the RF and IF PLLs and control the power modes of the device. The register is protected against SEU with a Hamming error correction mechanism. The SY1007 samples the DIO line on the falling edge of RCP. If requested to return data (read operation), the SY1007 will drive DIO and send data bits on RCP falling edge. At the end of a communication the DIO line goes low, the interface then remains idle as long as the DIO line is kept low. Figure 16, and tables 5 and 6 show the timing diagram of the serial interface. 11 Serial Interface tcp The SY1007 can be programmed via a single wire synchronous interface. The following can be accessed through the serial interface: • • • RCP tsu Power modes; RF PLL main divider; IF PLL main divider. All registers are read/write in order to allow reading back their contents for verification purposes. In case an error is detected (may happen only under a high radiation environment) the affected register needs to be rewritten. tpd DIO(W) T WR A0 DIO(R) T WR A0 D4 D4 tpZ D5 D5 D6 D6 tr D7 D7 tf Figure 16: Serial interface timing diagram. Name tcp tsu th tpdLH tpdHL tpZ tr tf 11.1 Communications Protocol Communication to the SY1007 occurs through a singlewire synchronous bidirectional interface (pin DIO) that is synchronous to RCP. The SY1007 works as a slave and never initiates a communication. A communication always consists of packets of two blocks: a control word and a data byte. Figure 17 shows a write and a read packet respectively. A packet consists of a start bit, followed by 6 bits (read) or 7 bits (write) depending on the operation requested, then by 8 data bits. The master device cannot abort an on-going packet. An aborted packet may cause register corruption. The control word – always sent by the master device (typically a SY1017) – specifies the kind of operation required (read or write) and the address of the register to be accessed. A communication is initiated by setting the DIO pin to logic 1 for one clock cycle. A parity bit (odd parity) is required, and in case a parity error occurs the operation is Parameter Clock cycle time Setup time Hold time Propagation delay L→H Propagation delay H→L Propagation delay to Z Output rise time, 10-90% Output fall time, 90-10% Min 200 15 Typ Max 4.0 5.5 4.0 3.6 3.3 0 8.5 7.6 7.0 6.1 4.8 Unit ns ns ns ns ns ns ns ns Table 5: Conditions: 2.2V, 125◦ C, Cl=5pF. Name tcp tsu th tpdLH tpdHL tpZ tr tf Parameter Clock cycle time Setup time Hold time Propagation delay L→H Propagation delay H→L Propagation delay to Z Output rise time, 10-90% Output fall time, 90-10% Min 200 10 Typ Max 2.4 4.0 2.4 3.4 2.8 0 6.4 5.7 5.5 4.9 3.8 Unit ns ns ns ns ns ns ns ns Table 6: Conditions: 3.0V, 125◦ C, Cl=5pF. RCP DIO(W) ST WR A0 A1 A2 P R DIO(R) ST WR A0 A1 A2 P R R D0 D0 D1 D1 D2 D2 D3 D3 D4 D4 D5 D5 D6 D6 D7 D7 Figure 17: SY1007 read and write packets. 10 Saphyrion Sagl Rev. 1.4, January 31, 2014 DATASHEET SY1007 GNSS RF Front-End 11.3 Packet Structure A packet consists of 2 blocks: a control word followed by a data byte. The structure of the control word is shown in table 7 and the meaning of the various fields in the control word is shown in table 8. Field Position Start 0 WR 1 Addr 2:4 P 5 Res 6(7) these locations results in no operation, in future versions it could results in temporary malfunctions. RW 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 Data 8:15 Table 7: Structure of the control word. Field Start WR Addr[0:2] P Res Data[0:7] Description Must go HIGH to start communication. Transfer direction: 0 : READ operation. 1 : WRITE operation. Register address, LSB first (see table 9). Parity. It is calculated on Start bit, Write and Address fields. Parity is ODD, i.e. the number of 1’s in bits [4:0] of the control word must be odd. Reserved (1 bit for read, 2 bit for write). Write operation: the master sends the data to be written in register. Read operation: the SY1007 returns the register content. Table 8: Description of the control word. 11.4 Parity Check As a means to prevent registers corruption during write under a high radiation environment, parity check is performed on the control word. Parity is calculated on the valid fields of the control word, i.e. Start, WR and Addr[0:2]. The Res[0:1] bits are not used to calculate parity. The expected parity type is odd, i.e. the total number of 1’s in bits [0:5] of the control word must be odd. If a parity error is detected during a write operation, e.g. a SEU occurs, that operation is immediately aborted, i.e. the data is discarded and the corresponding register is not updated. The parity bit is ignored during a read operation, i.e. the data is returned regardless of the value of the parity bit. It is highly recommended that every write is followed by a read operation to verify that the write actually succeeded and that the written value is the intended one. 12 Register File 12.1 Register Map The register map is reported in table 9. Register locations marked as Reserved are reserved for future developments. To maintain compatibility with new releases of the SY1007 no attempt should be made to access these locations. While in the current release an attempt to access Address A1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 A0 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 A2 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 Dir Register R R R R R R R R W W W W W W W W RF-PLL (8-bit) Reserved Pwr-Modes (2-bit) Reserved IF-PLL (8-bit) Reserved Reserved Reserved RF-PLL (8-bit) Reserved Pwr-Modes (2-bit) Reserved IF-PLL (8-bit) Reserved Reserved Reserved Table 9: Register map. 12.2 Register Fields The meaning of the fields of all registers is shown in table 10. The fields marked as Reserved are reserved for future developments. To maintain compatibility with new releases of the SY1007 it is recommended that these fields are written with zeros. When read back these fields return zeros. The content of all registers is undefined until written, there is no default value. 12.3 Hamming Error Correction As a means to protect the register’s content from single event upset (SEU) errors that may occur under high radiation, Hamming error correction has been implemented on all registers. This error correction mechanism is able to correct up to one error per register per clock cycle. To implement Hamming error correction 12-bit registers are used, as shown in figure 18. Each register holds the actual data value and 4 check-sum bits. During a register write cycle the new check-sum is computed by the generation matrix and stored in the register together with the actual data. Error-correction occurs on each clock cycle (except during register write cycle). The correction matrix computes corrected data out of the data stored in the 12 bit registers and rewrites it back at the following clock falling edge, thus removing any single SEU error. Every register has its independent error correction system, thus several simultaneous errors will be corrected as long as they occur in different registers. Register Pwr-Modes Bits 0:1 Count 2 Field Power Modes RF-PLL 2:7 0:7 6 8 (Reserved) RF-PLL Divider IF-PLL 0:7 8 IF-PLL Divider Description 00=Sleep 01=Doze 11=Stand-By 10=Fully active Currently ignored, set to 0 RF-PLL division factor: D0 20 + D1 21 + · · · + D7 27 IF-PLL division factor: D0 20 + D1 21 + · · · + D7 27 Type RW N/A RW RW Table 10: Register fields description. Rev. 1.4, January 31, 2014 Saphyrion Sagl 11 DATASHEET DI[7:0] SY1007 GNSS RF Front-End Hamming Code Generator 0 C[3:0] Hamming Code [3:0] 1 1 Data [7:0] Error Correction DO[7:0] D[7:0] 0 WR RCP Figure 18: Hamming error correction register. The various circuit blocks of the SY1007 receive data directly from the correction matrix rather than from the output of the registers. This ensures that in case of a SEU error the correct value is available immediately within a combinational delay and not with a clock cycle latency. Glitch suppression logic removes the eventual error correction glitch, as well as single event transient (SET) glitches. During a read operation, if a SEU occurs in the same clock cycle when data is latched by the read shift register, the incorrect value might be returned back, although the content of the register itself will be corrected on the next clock cycle. 13 Applications Information 13.1 Power Control The SY1007 provides 4 different power modes that can be used to implement various power saving methods. These power modes are listed in Table 11 and their purpose is the following: • Sleep: In sleep mode all circuits of the SY1007 are powered down. In this mode, the registers can still be read or written. Power consumption will mainly depend on the input clock frequency and the number of accesses that are made to the registers. If the clock frequency is set to zero, the power consumption consists mainly of leakage currents. • Doze: In doze mode the band-gap reference and the voltage regulator are turned on. The time required to enter this state is dominated by the time required by the voltage regulator to turn on. With a 33µF capacitor it approximately 50ms. • Stand-By: In stand-by mode the PLL is turned on while the signal path stays powered down. This state may be used to allow the PLL to stabilize before entering the fully active mode. • Fully active: In fully active mode the SY1007 is fully on and operating. The power modes of the SY1007 may be selected via the digital interface by writing in the Pwr-Modes register (bits [0:1], see table 10). Table 11 shows the approximate time required to reach stable operation (latency) from the previous state. Exiting any power mode is much faster and typically takes less than 100µs. Gray coding has been used to simplify avoiding glitches while switching from one power mode to the other. Switching from one power mode to the other may be done in any order. 12 Mode Sleep Doze Stand-By Code 00 01 11 Fully Active 10 Latency 50ms 5-10ms (depends PLL loop filter) 150-250µs on Table 11: SY1007 power modes. 13.2 Frequency Plans Since the SY1007 has independent RF and IF local oscillators, it offers a great freedom in the selection of frequency plans. Basically, any frequency plan that places the IF somewhere around 100-300MHz and the near base-band signal bandwidth inside the I/Q filter bandwidth (12MHz worst-case) is potentially suitable. In the interest of reducing the PLL spurious content a high reference frequency can be used. The limiting factor is however the resolution of the integer-N PLLs that is 4x RCP for the RF PLL and RCP for the IF PLL. Using excessively high reference frequencies may prevent good frequency plans to be designed. Table 12 shows a few frequency plans examples that can be implemented using the on-chip PLLs. In these examples the use of either a common RF or IF local oscillator frequency has been assumed together with a reference frequency of 5MHz. This gives a resolution of 20MHz and 5MHz for the RF PLL and IF PLL respectively. Using a common IF frequency may simplify the design of the IF filters, as one single filter type may serve several bands. The performances of the SY1007’s on-chip PLLs were tailored for generic GNSS navigation receivers. For more critical applications requiring better phase noise than the SY1007 can offer, external local oscillators can be used. In the interest of reducing the effect of phase noise, in multichannel receivers it is best to share the signal of a single low-noise local oscillator among all channels rather than regenerating the local oscillator signals locally. The phase noise will then be coherent on all channels, such that it can be rejected as a common-mode signal. Good frequency plans with shared local oscillators may be achieved e.g. by using a common RF local oscillator frequency of 1400MHz, as shown in table 12. A single external RF PLL would then be required, while the on-chip IF PLLs can still be used. A phase noise improvement of up to approximately 20dB at offsets below 100Hz may be achieved this way, without requiring any external IF PLLs. Saphyrion Sagl Rev. 1.4, January 31, 2014 DATASHEET SY1007 GNSS RF Front-End 13.3 Analog Blocks 13.3.1 Low Noise Amplifier (LNA) The LNA requires matching networks at its input and output. Figure 19 depicts a typical configuration for the LNA with its matching networks. AVDD L2 C2 RF IN R1 L1 LNA LNI 100pF LNO L3 C3 100pF RF OUT Band Frequency C1 L1 L2 L3 R1 Gain NF S11 S22 L1/E1 1575MHz N/F 3.9nH 5.6nH 6.8nH N/F 18.9dB 1.6dB −2.6dB −14.6dB L2 1227MHz N/F 6.8nH 12nH 12nH N/F 20.4dB 1.5dB −2.1dB −23.1dB L5/E5a 1176MHz N/F 6.8nH 15nH 12nH N/F 21.2dB 1.4dB −1.9dB −23.3dB Table 13: Noise matching networks. C1 Figure 19: LNA configuration (matching networks). Depending of the type of signal source used (antenna, external LNA), the input of the LNA may need to be configured for noise matching or for impedance matching, while the output of the LNA – which typically is connected to a SAW filter – needs to be impedance matched to 50Ω. Tables 13 and 14 show typical values for the matching networks and the resulting LNA performances, obtained on the SY1007 test board. For the impedance-matched case a RLC network has been proposed in order to broaden the impedance matching bandwidth. The 100Ω resistor will however increase the noise figure by about 1.5dB, which is usually acceptable if sufficient gain is placed in front of the SY1007’s LNA. If the gain of the external LNA is above ≈25dB an attenuator can be used to further improve matching and achieve a higher interferer resilience. As with any GHz RF circuit, RLC component types and design of the PCB are critical to the performances of the LNA. Proper RF PCB design is needed, while components with size 0805 or smaller shall be used. The values of all matching components depend on the layout of the PCB or the substrate dielectric constant. The component values shown in Tables 13 and 14 have been found experimentally on the SY1007 test board and may (will) vary and require optimization. LNA S-parameters in Touchstone format are available. Band Frequency C1 L1 L2 L3 R1 Gain NF S11 S22 L1/E1 1575MHz 3.3pF 4.7nH 5.6nH 6.8nH 100Ω 20.0dB 4.5dB −17.6dB −12.6dB L2 1227MHz 3.3pF 8.2nH 12nH 12nH 100Ω 22.5dB 3.5dB −16.13dB −13.6dB L5/E5a 1176MHz 3.3pF 10nH 15nH 12nH 100Ω 21.0dB 4.2dB −21.3dB −13.2dB Table 14: Impedance matching networks. Coupling between LNI and LNO shall be minimized. Stray inductances and capacitances will create a Hartley oscillator tank-circuit around the LNA. If the capacitance between LNI and LNO is not minimized the LNA will break into sustained oscillation. A ground track running between LNI and LNO is usually needed. Please make also sure that AVDD is very well decoupled. Any stray impedance on AVDD will appear in series with L2, thus upsetting output matching. In systems having a gain >30-35dB in front of the SY1007, the on-chip LNA may not be necessary or may even lead to poor front-end linearity if used. In such cases the on-chip LNA may be disabled by tying its input (LNI) to ground and leaving its output (LNO) open. In such case no components need to be mounted around the LNA. GNSS signal GNSS Freq. LO freq. IF1 IF2 20-25MHz Signals, RCP=5.0MHz, RF-LO=1400MHz, fs=40-50MHz GPS L1, GAL E1bc 1575.42MHz 175MHz 175.42MHz 0.42MHz GLO L1 1601.71MHz 200MHz 201.71MHz 1.71MHz GPS L2 1227.60MHz 170MHz 172.40MHz 2.40MHz GLO L2 1245.78MHz 155MHz 154.22MHz 0.78MHz GPS L5, GAL E5a 1176.45MHz 225MHz 223.55MHz 1.45MHz GAL E5b 1207.14MHz 195MHz 192.86MHz 2.14MHz GAL E6 (BPSK5) 1278.80MHz 120MHz 121.20MHz 1.20MHz 20-25MHz Signals, RCP=5.0MHz, IF-LO=175MHz (⇒IF-VCO=350MHz), fs=40-50MHz GPS L1, GAL E1bc 1575.42MHz 1400MHz 175.42MHz 0.42MHz GLO L1 1601.71MHz 1420MHz 181.71MHz 6.71MHz GPS L2 1227.60MHz 1400MHz 172.40MHz 2.60MHz GLO L2 1245.78MHz 1420MHz 174.22MHz 0.78MHz GAL E5b 1207.14MHz 1380MHz 172.86MHz 2.14MHz GAL E6 (BPSK5) 1278.80MHz 1460MHz 181.20MHz 6.20MHz Table 12: Some possible frequency plans (for GPS, GALILEO and GLONASS). Rev. 1.4, January 31, 2014 Saphyrion Sagl 13 DATASHEET 13.3.2 SY1007 GNSS RF Front-End An RF filter is always required with the SY1007, in order to remove out-of-band signals that could disturb chip performance. A filter with sufficient selectivity to suit the operating environment should be chosen. The most important filter parameters to look at are: • • • Attenuation of the image frequency (≥20dB recommended). Attenuation of signals from on-board transmitters. Insertion loss, especially if passive antennas and no external LNAs are used (≤2.5dB recommended). Either SAW filters or dielectric filters may be used as long as sufficient performances are available. Suitable filters can be found e.g. by Vectron, ComDev or Norspace, in some cases already qualified for Space use (ESCC 9000 or MIL-STD-883 Class S). The PCB layout around the RF filter is critical to filter performance. Input and output of the filter shall be very well isolated, otherwise the RF signal would be allowed to bypass the filter, thus compromising its out-of-band rejection. Figure 20 shows a possible PCB layout (for a SAW filter in LCC package). A fence between filter’s input and output – well connected to the ground plane with several vias – minimizes capacitive coupling that would bypass the filter. Ground Ground IN OUT Ground Ground Figure 20: Suggested SAW filter PCB layout. 13.3.3 Band Low, 1.2GHz (L2-L5) High, 1.6GHz (L1) RF Filter (SAW or Dielectric) RF Mixer Input C 2.7pF 2.0pF L 6.8nH 5.6nH Table 15: Component values for LC balun. Again – as usual with RF designs – good PCB RF layout is necessary, as any stray impedance will upset input matching, reduce the conversion gain of the mixer and worsen its noise figure. The input of the RF mixer is biased to about 400mV and shall never be DC shorted to ground or receive any DC biasing from outside, otherwise the SY1007 will be permanently damaged. If the RF filter or balun has a DC path to ground DC blocking series capacitors shall be used. Such capacitors may also be used to compensate possible stray inductance of the PCB trace; as a starting point the recommended value is 18pF, which should then be optimized experimentally. 13.3.4 IF Filter The SY1007 requires an external IF filter for channel selection and to filter off noise at the images of the ADconverter. Various IF filter types may be accommodated by the SY1007 in order to suit different operating conditions. When selecting an appropriate IF filter it is however important to consider that all receiver’s filtering requirements shall be implemented by the RF and IF filters, before the high gain IF-strip, otherwise poor receiver performances may result. Although the SY1007 accommodates various IF-filter types, in most cases a 4th or 6th order bandpass LC-filter is used. Figure 22 shows the schematic diagram of such filter. It consists of a parallel resonator (L1-C1, implementing 2 poles of the filter) followed by a coupled resonator 4th order stage (L2-C2, L3-C3-R3 and the coupling capacitors C4-C5). The RF mixer input is 50Ω balanced and can typically be connected directly to either a SAW filter (with balanced output) or to a 1:1 balun. Suitable baluns for the SY1007 are transformer, transmission line or discrete LC designs. LC baluns may be preferable since they use simple LC parts readily available in space-qualified quality. R3 L1 L2 L3 C4 C1 C3 C5 C2 C C MIXP L RF-IN Unbal. (50Ω) Mixer IF2N IF Amp IF VC Amp Figure 22: IF LC-filter configuration. C Figure 21: LC balun schematic diagram. A possible LC balun structure is shown in Figure 21. Since an LC balun is selective, the values of the components must be adapted to the operating frequency of the balun. In order to cover all GNSS bands two designs are sufficient. Table 15 shows the LC values for these two designs (low and high band), which must be adjusted experimentally to fit PCB parasitics. 14 IF1N IF2P RFN RFP RF-OUT Balanced (50Ω) L C MIXN IF1P The whole IF filter is best considered as a single filter (rather than separate filters) and may be calculated with readily available computer programs or using filter tables. Since the input impedance of the VCA is high, resistor R3 is necessary if a 6th order filter is to be implemented. This resistor however causes the insertion loss of the filter to increase. In order to avoid an excessive insertion loss that can no longer be compensated by the IF VCA this resistor should be selected to be ≥600Ω. A good starting point could be 1.0-1.5kΩ. A 600Ω resistor already results in an extra 6dB insertion loss. Saphyrion Sagl Rev. 1.4, January 31, 2014 DATASHEET SY1007 GNSS RF Front-End In many cases a 4th order filter is sufficient. In this case C4 and C5 shall be set to 100pF and C3-L3-R3 omitted. 4th order IF filters for 3 different IF frequencies are shown in the application example (Section 16, Figure 29). Figure 23 shows a measured frequency response (from 120MHz to 220MHz) of the 4th order 174MHz IF filter of the application example. both I and Q outputs. Traces with equal length and width should be used as well. C1 100nF OIP OIN SY1007 SY1008 C2 100nF I1N C3 100nF OQP OQN I1P C4 I0P SY1017 I0N 100nF AGCI AGCO C5 174MHz IF Filter 1.0nF 10 Figure 24: Typical SY1007 to SY1017 interface. 5 0 Amplitude 5.0 dB/ −5 −10 −15 −20 −25 −30 −35 −40 120 130 140 150 160 170 180 190 200 210 220 Center 170.0 MHz Span 20.0 MHz #Res BW 1.0 MHz VBW 1.0 MHz Sweep 401 pts Figure 23: Measured 4th order IF-filter response. Accurate, temperature stable components shall be used in the IF filter. Ceramic NPO capacitors with 2% (maximum 5%) tolerance are recommended. Placing two capacitors in parallel as shown in Figure 29 allows an easy fine tuning of the IF filter. Wire-wound or multi-layer inductors (again with maximum 5% tolerance) can be used for values below about 500nH, while shielded ferrite-core inductors are useful for higher values. Unshielded opencore ferrite inductors shall never be used in the IF filter. Open-core ferrite inductors are in fact efficient antennas (rod antennas) that would easily pick-up any interference around the frequency to which the IF filter is tuned. 13.3.5 IF-Strip and Quadrature Output The IF-strip of the SY1007 comprises a VCA with logarithmic (dB-linear) control input and a quadrature downconverter. The gain of the VCA is controlled by the voltage applied to pin ACGI, which is typically obtained with the DA-converter of a SY1017. When used in combination with the SY1017 a gain step of about 1dB is obtained. If a different device is used to generate the AGC control voltage it must be able to produce a V(AGCI) = 0.2V to 2V in order to cover the whole gain control range. Please observe the temperature dependence of gain vs. V(AGCI), Fig. 8. Since the AGC control is rather sensitive (about 9mV/dB) the control voltage shall be kept clean, otherwise gain modulation will occur. An RC low-pass filter may be used to reduce possible noise on pin AGCI. The near base-band quadrature output is available on pins OIP, OIN, OQP, OQN. Typically these outputs are ACcoupled to a SY1017 AD-converter ASIC, as shown in Fig. 24. 100nF ceramic X7R (or better) capacitors are recommended. These outputs are filtered with on-chip 3rd order lowpass filters and are internally buffered with low output impedance (about 125Ω) amplifiers to minimize errors due to loading effects. In order to keep amplitude and phase errors low it is however mandatory that load impedances – including PCB strays – are kept as similar as possible on Rev. 1.4, January 31, 2014 Although the output impedance of the I/Q outputs is 125Ω, this does not mean that they can drive a 125Ω load. OIP-OIN and OQP-OQN shall in fact not be loaded with less than 10kΩ, or severe distortion and amplitude limiting will occur. Adding base-band off-chip filtering on the I and Q outputs as a means to improve channel filtering is strongly NOT RECOMMENDED. Such filtering – if used – will introduce quadrature errors (unless the filters are carefully aligned) and will very likely cause AGC misbehavior or receiver blocking in presence of near-band interferers. If base-band filtering is required please make sure that any and all interferers are removed at RF and IF, before they can reach the high gain IF-strip (pins IF2P-IF2N). 13.3.6 RF and IF Frequency Synthesizers The SY1007 contains two frequency synthesizers which generate the required RF and IF local oscillator signals. RF and IF PLLs are enabled with pins RENB and IENB (active on low logic level) respectively, and can be enabled or disabled independently from each other. Both RF and IF synthesizers need an off-chip inductor for the VCO, whose value depends on the required local oscillator frequency and that shall be adjusted depending on PCB strays. In order to align the PLL, a VCO inductor value of 4.7nH and 47nH respectively can be used as starting point, then the reference frequency of the PLL shall be swept and the loop filter voltage measured and recorded. Curves similar to the ones shown in Figures 9 and 10 (Section 7) should be obtained. The VCO inductors shall then be adjusted (replaced) until the PLL operating point is in the middle of the measured PLL curve. The Q of the inductors is instrumental in obtaining reasonable VCO performances and phase noise. If inductors with excessively low Q are used phase noise will increase, while the VCO may even stop operating, especially at the higher temperature limit. If such behavior is noticed inductors with higher Q shall be used. Caution: great attention has to be paid to the PCB layout around the VCO inductors, especially the one of the RF VCO. The shortest, straightest tracks shall be used to connect the inductor to the SY1007, otherwise the desired VCO frequency may not be attainable with any inductor value, or spurious oscillations, not defined by the VCO inductor, may result. The stray inductance of the PCB traces connecting the inductor to the RF VCO shall be evaluated if inductors below about 2.7nH are required to reach the proper VCO operating frequency, or if the SY1007 RF PLL fails to lock or behaves in a strange manner. Please remember that 1nH (about 1.2-1.5mm PCB track) and 1pF (a small PCB area, 2-3 footprints) at 1.6GHz are already a reactance of 10Ω and 100Ω respectively. Saphyrion Sagl 15 DATASHEET 13.3.7 SY1007 GNSS RF Front-End 13.3.8 RF and IF PLL Loop Filters The loop filters for the RF and IF PLLs are external and shall be connected to pins RPLL and IPLL respectively. A CRC network, as shown in Figure 25, is recommended. The components can be calculated using the VCO sensitivity data and the desired division ratio. The nominal current of the charge pump is 50µA. RPLL, IPLL External Local Oscillators In applications that require better phase noise than the SY1007 can offer, the SY1007’s on-chip PLLs can be disabled by setting RENB or IENB to logic high and external oscillators can be used instead. The signal of a balanced external oscillator shall be applied to pins RL1-RL2 (RFVCO) and/or IL1-IL2 (IF-VCO). The external RF-VCO shall be set to the desired RF-LO frequency, while the external IF-VCO shall be set to twice the desired IF-LO frequency to account for the dividing-by-two quadrature LO generator (see Section 10 and Figure 15). C2 C1 xL1 SY1007 SY1007 R1 xL2 xL1 xL2 C1 Figure 25: PLL loop filter schematic diagram. The cut-off frequency of the loop filter is a trade-off between phase noise and spurious signals power, and should therefore be dimensioned according to the needs of the given application. Figure 26 shows schematically the idealized behavior of the phase noise of the SY1007’s RF PLL for two different loop filter bandwidths (purple: wideband, red: narrow band loop filter) as well as the contributions of the VCO and the charge pump alone. -50 VCO phase noise (free running) -3d B/o ct. -70 Charge pump thermal noise -80 Charge pump flicker noise /o dB -6 -90 . ct Phase noise [dBc/Hz] -60 -100 -110 100 1k 10k 100k 1M Frequency offset [Hz] Figure 26: Phase noise of RF PLL (idealized). A wide-band loop filter (faster PLL, purple curve) gives better phase noise performances at the expense of higher spurious signals. In contrast, a narrow-band loop filter attenuates the spurious signals to the detriment of the phase noise performance (slower PLL, red curve). A phase margin around 50-55◦ is recommended if fast lock time is desired, otherwise lower phase margins can be used if spurious signals have to be reduced. Examples of loop filter designs are shown in the application example (Section 16). The loop filter – or at least C2 (in Figure 25) – should be mounted close to the RPLL and IPLL pins in order to provide a low inductance RF path to ground. PCB tracks carrying noisy signals (e.g. digital lines) should be kept away from the loop filter, otherwise noise could be injected into the PLL, thus degrading phase noise performances by directly modulating the VCO. 16 1nF Transmission line (balanced, 100Ω) R1 100Ω C2 1nF Figure 27: LO distribution (bridging). The VCO inputs are high impedance and may be terminated with an inductor to compensate their input capacitance if necessary. These inputs are internally biased to AVDD and shall not be forced. A termination resistor may also be used to properly terminate the LO transmission line if necessary. If an on-chip PLL is disabled no loop filter is required on its respective pin (RPLL or IPLL). In that case these pins shall be left open and no connection shall be made to them. Pins RPLL and IPLL are internally biased (to AVDD) when on-chip PLLs are disabled and shall not be forced. In systems using many RF channels in parallel that share the same local oscillator frequencies, the local oscillator signals can be distributed in a simple and effective way using a single transmission line as shown in Figure 27. This LO signal sharing structure is possible thanks to the high input impedance of the SY1007’s LO inputs. The transmission line – e.g. 100Ω – shall be terminated at its end, while the taps to the SY1007 shall be very short to avoid stubs that would cause line mismatch. By bridging many SY1007 on the same transmission line lossy power splitters are avoided and the LO power can be lower. With careful PCB layout, up to 4-5 SY1007 can be bridged on a single transmission line. Please observe the signal level requirements (Section 5 and Note 15). 13.4 Voltage Reference and Regulator Biasing to the SY1007 is provided by an on-chip 1.17V band-gap voltage reference and a 1.9V voltage regulator. These voltages are available on pins VBG and VB respectively. The 1.9V regulator provides power to the VCO. Both band-gap reference and voltage regulator are active in doze mode and up. A capacitor of at least 1µF (ceramic X5R or X7R) is required for stability on both VBG and VB, which shall be mounted close to the chip. To improve noise performances, in particular the phase noise of the VCO, a capacitor of at least 33µF is recommended for VBG. Saphyrion Sagl Rev. 1.4, January 31, 2014 DATASHEET SY1007 GNSS RF Front-End Both outputs may supply power to an external load if desired. The maximum available output current is 200µA and 1mA respectively. It is however important that these loads, if used, do not introduce any noise into VBG and VB. In particular, noise into VBG may disturb the whole chip, while noise into VB may disturb especially VCO and PLL. 13.5 Power Supply The SY1007 requires two power supplies: analog (AVDD) and digital (DVDD). The recommended ranges are shown in Table 16. The power supplies need not be well regulated but must be well filtered. This applies in particular to the analog power supply AVDD. DVDD may be taken either from AVDD via an RC or LC network or from some other (clean) voltage. Using a general power supply – e.g. the power supply for some micro-controller or GNSS base-band processor – as DVDD is not recommended, as digital switching noise would be injected into the SY1007 thus degrading its performance. Power Supply AVDD (Analog) DVDD (Digital) Min 2.4V 2.2V Max 3.6V AVDD+0.2V Table 16: Power supply ranges. No particular sequencing is needed while applying power to the SY1007. AVDD and DVDD may be applied simultaneously or in any order. Increasing DVDD above its maximum operating level (AVDD+0.2V) is not recommended except during the power on transient. This will not cause any permanent damage, but the SY1007 will not operate correctly if the condition is violated. Once DVDD is returned to the allowed range the SY1007 will resume proper operation from itself while no data is lost if DVDD is kept above its minimum rating of 2.2V. Signal voltages shall not be applied to the SY1007 before the power supply is applied, otherwise the ESD protection diodes may become forward biased and possibly be damaged. Digital signals may track DVDD during power transients, as long as the DVDD+0.2V condition is not violated. Power supply decoupling is always required. A 100nF ceramic capacitor (X7R) mounted very close to the device body is recommended on each AVDD and DVDD pins. A 2.2µF (or higher) ceramic or tantalum capacitor may be required on AVDD, especially if AVDD is not well regulated. A 1nF capacitor has to be mounted very close to the LNA output matching network on the AVDD supply. 14 Handling Precautions 14.1 Hazardous Substances The SY1007’s solder balls contain lead (Sn60-Pb40), therefore the SY1007 is not RoHS compliant and shall be handled accordingly. Discarded SY1007 devices shall not be dispersed into the environment or disposed of with common waste. Apart from the lead contained in the solder balls, the SY1007 does not contain any other hazardous materials, in particular no mercury (Hg), cadmium (Cd) or Rev. 1.4, January 31, 2014 hexavalent chromium (Cr6+), the flame retardants polybrominated biphenyls (PBB) and polybrominated diphenyl ethers (PBDE), or berillium oxide (BeO) ceramic. 14.2 Storage The SY1007 is packaged in a ceramic-metal package that is not sensitive to humidity, however improper storage may cause contamination or oxidation of the solder balls thus impacting solderability. The product shall not be exposed to high humidity or to direct sunlight, harmful/corrosive gases or dust. Also avoid storing it in locations where sudden temperature changes may occur. To ensure long shelf life, the product should be stored in a controlled temperature (≈20-25◦ C) and humidity (<60%) environment, possibly in its original shipping bag. Do not open the bag until just before product’s use. If longterm storage of several years is anticipated, the product should be stored in a dry cabinet. 15 Radiation Tolerance The SY1007 is a rad-hard device and several countermeasures have been taken during its design to achieve a high degree of radiation tolerance. The extensive use of guard rings and other latch-up prevention techniques – especially in the I/O area – yields excellent latch-up immunity. 2 have proven the Heavy ion tests up to a LET of 45MeV cm mg chip’s robustness against both latch-up and SEU. Several DUTs have been tested at temperatures up to 85◦ C and a maximum supply voltage of 3.6V until a cumulated fluence of 1E+7 ions/cm2 without detecting any latch-up. 2 If requirements higher than 45MeV cm have to be fulmg filled some latch-up protection is required. This may consist of a current limited (40-50mA) voltage regulator with a fast acting disable function to release the latch-up. Specific latch-up protection circuits are also available on the market, which can be used with the SY1007. The total decoupling capacitor on the SY1007’s power supply shall be limited to <10µF to avoid burn-out of the SY1007 due to the capacitor surge. All registers are protected against SEU with a Hamming error correction mechanism, while a parity bit protects communications from the master device to the SY1007. It is however good practice not to rely on the built-in SEU protection alone. It is recommended that after a write operation a read operation to the same register is performed, while all registers should periodically be read back to check their contents. If corrupted data is found then re-read the register, if the data is still wrong then rewrite the register and check it again. Checking back the registers is the first thing to do in case of suspicion of configuration loss of the device (e.g. if the receiver stops working suddenly). Since the RF-PLL register remains selected when the SY1007’s interface is idle, accessing it at the end of a register verification operation further minimizes risks of SEU. The SY1007 comes into a ceramic-metal hermetic package containing no organic materials, while eutectic – rather than epoxy – die attach has been used. This device will therefore not decompose or release any substantial amount of gas or organic contaminants under vacuum or high radiation levels. Saphyrion Sagl 17 DATASHEET 16 SY1007 GNSS RF Front-End Application Example Figure 28: Application example: top level. 18 Saphyrion Sagl Rev. 1.4, January 31, 2014 DATASHEET SY1007 GNSS RF Front-End Figure 29: Application example: RF section (SY1007). Rev. 1.4, January 31, 2014 Saphyrion Sagl 19 DATASHEET SY1007 GNSS RF Front-End Figure 30: Application example: AD-converter section (SY1017C). 20 Saphyrion Sagl Rev. 1.4, January 31, 2014 DATASHEET 17 SY1007 GNSS RF Front-End Layout Recommendations 18 The SY1007 is a sensitive receiver. Although the IC is rather robust and easy to use, an improper PCB layout may degrade its performance significantly. The best performance is generally achieved when the SY1007 is placed over a solid ground plane with as little interruptions as possible. If a 2 layer PCB is used, the best layout would be to use the bottom layer as ground plane with all routing made on the top layer. A similar layout can be used also in multilayer PCBs, where internal layers can be used as ground plane instead of the bottom layer. It is however recommended to leave some spacing (at least 0.3mm) between the top layer and the ground plane, as this reduces losses and stray capacitances. A core laminate rather than a pre-preg should be used in order to obtain a better control on thickness and thus on transmission lines impedance. Standard PCB materials such as FR4 can be used. Special low-loss substrates are in most cases not required to achieve proper performance, and would give only moderate performance improvements. Proper connections are also important if good performance is to be achieved. The RF connections to the antenna and SAW filter shall be made with 50Ω striplines (unless their length does not exceed a couple mm), while vias on all RF connections shall be avoided. Decoupling capacitors – especially on AVDD and VB – shall be connected very close to the chip using traces as wide as possible, with the other side of the capacitor well grounded (23 vias). AVSS and DVSS shall be connected to the ground plane as close to the chip package as possible. In order to avoid interference to the receiver from digital switching noise all digital signals shall be routed away from sensitive analog connections while some shielding is recommended. In particular the SY1007 shall be placed in its own shield or cavity, well separated from any digital component (including the SY1017C). The components most sensitive to interference are the antenna and the LNA, followed by the IF filter. U1-SY10xx PCB Recommendations To guarantee proper mounting of the IC, the PCB land pattern shown in Figure 31a shall be used. In particular the following requirements shall be adhered to: • Non solder mask defined (NSMD) lands shall be preferred. • The width of the fan-out traces shall not exceed 0.3mm and shall be symmetrical to avoid part rotation due to surface tension of solder. • Vias inside PCB lands (preferred) shall be plugged and metallized on top to prevent solder from wicking through the via hole. Unplugged vias inside PCB lands are not allowed. • If used, a solder mask with tight openings is recommended to ensure that some solder mask remains between the PCB lands. Traces passing between lands shall be completely covered with solder mask, otherwise short-circuits may easily develop. Putting the solder mask only under the SY1007 is also possible if covering the whole PCB is not allowed. • If PCB flexing is likely, the part should be placed on an unstressed area, away from the area of maximum flexing, otherwise solder joints may crack. • The PCB shall meet the solderability requirements of IPC/JEDEC J-STD-003 and shall be flat to within 0.1mm per cm. Surface finishes such as an organic solderability preservative (OSP) coating or Sn and Ni-Au finishes are fine, while hot air solder leveled (HASL) finish is not recommended. • If a Ni-Au finish is chosen (electroplated Ni, immersion Au), Au thickness must be less than 0.2µm to avoid solder joint embrittlement. PCB Gerber data is available and can be used as recommended layout. To request it please contact SAPHYRION support team at support@saphyrion.ch. Solder Mask PCB Land ≅0.05 Stencil 0.80 BSC a. 0.80 BSC 0.80 o0.45 −+0.05 0.80 0.35 b. Figure 31: PCB land pattern and stencil openings: BGA, 6mm x 6mm, 36 balls. Rev. 1.4, January 31, 2014 Saphyrion Sagl 21 DATASHEET 19 SY1007 GNSS RF Front-End Mounting Recommendations • The standard JEDEC (J-STD-020) reflow temperature profile shown in Fig. 32 should be used. The recommendations given by the solder paste manufacturer should also be followed. The SY1007 is fitted with Sn 60%-Pb 40% solder balls (melting point = 183◦ C). The device shall be mounted to the PCB by reflow soldering. Infra-red (IR) reflow is the preferred method, vapor-phase reflow may also be used however. Please follow these recommendations: Typically, the area under the profile curve, bounded by the liquidus temperature, defines the quality of the solder joint. Too little area leads to cold solder joints, which are a reliability risk. Too much area could result in undesirable metallurgical issues, that could also be a reliability risk. Some experimentation may be necessary. A daisy-chain device that can be used to validate the soldering process for the SY1007 is available. After assembly the board shall be cleaned to remove solder flux residue. Solder flux residue between pads or on RF components may cause high leakages which may increase RF losses to an unacceptable level. Ultrasonic cleaning shall not be used since many parts – especially crystals, SAW filters and oscillators – may be damaged. No-clean solder flux may be used to minimize cleaning requirements. • Stainless steel stencils with a thickness of 100125µm are recommended for solder paste application. For improved solder paste release the walls of the apertures should be tapered and the corners rounded. • The recommended stencil apertures are shown in Fig. 31b. Use laser cutting followed by electropolishing for stencil fabrication. Etched stencils are not recommended. • Use Type 3 (25µm to 45µm particle size range) or finer solder paste for printing. (Near) eutectic Sn60Pb40, Sn63-Pb37 or Sn62-Pb36-Ag2 solder pastes with a melting point of 183◦ C shall be used. Profile Feature Preheat/soak: Temperature Min (TSmin ) Temperature Max (TSmax ) Time (tSmin to tSmax ) Reflow: Ramp-up rate (TL to Tp ) Liquidus temperature (TL ) Time (tL ) maintained above TL Peak temperature (Tp ) Time whitin 5◦ C of actual peak temperature Tp (tp ) Ramp-down rate (Tp to TL ) Time 25◦ C to peak temperature Sn-Pb Eutectic Assembly 100◦ C 150◦ C 60s to 120s 3◦ C/s max. 183◦ C 60s to 150s 240◦ C 10s to 30s 6◦ C/s max. 6 minutes max. Table 18: Reflow profile details (JEDEC J-STD-020). tp Tp Ramp down Ramp up Temperature [ C] TL TS max TS min tL tS t 25[ C] to Peak Temperature Time [s] Figure 32: Recommended reflow profile. 22 Saphyrion Sagl Rev. 1.4, January 31, 2014 4 3 2 0.85 C0.1 R4.7 C0.08 D A C 5x0.8=4 0.72 C0.07 0.8 D A Package Drawing R5.6 C0.05 1 DATASHEET 5 R6 C0.15 20 Rev. 1.4, January 31, 2014 6 C Saphyrion Sagl SOLDER LID 42 ALLOY / Solder KC-003 A-A B B Customer 6 5 4 Name 36 CSP KF-2007037-REF Drawing no. EUROPEAN DESIGN CENTRE CONFIDENTIAL INFORMATION ALL RIGHTS RESERVED. PASSING ON AND COPYING OF THIS DOCUMENT, USE AND COMMUNICATION OF ITS CONTENTS NOT PERMITTED WITHOUT WRITTEN AUTHORIZATION FROM KYOCERA. 3 Scale A3 16:1 File2007037 name - 36 csp assy.iam 2 Issue 0 Date 30/03/2007 A NOTES : 1. CERAMIC MADE BASED ON KYOCERA DRWG KD-UA4K32 2. SODLER LID MADE BASED ON KYOCERA DRWG KKM-30017-01 3. BALL ARE FOR REFERENCE ONLY Designed by David Checked by Sheet 1 1/1 A 23 SY1007 GNSS RF Front-End CERAMIC KYOCERA A473 DATASHEET SY1007 GNSS RF Front-End Glossary Acronym AGC AGGA (C)BGA EM/FM ESA ESCC ESD GLONASS GNSS GPS HBM HBT IF LET Meaning Automatic Gain Control Advanced GPS/GLONASS ASIC (Ceramic) Ball Grid Array Engineering Model / Flight Model European Space Agency European Space Components Coordination Electro-Static Discharge GLObalnaya NAvigatsionnaya Sputnikovaya Sistema Global Navigation Satellite System Global Positioning System (NAVSTAR) Human Body Model (ESD) Heterojunction Bipolar Transistor Intermediate Frequency Linear Energy Transfer Acronym LNA LO NF OCXO PCB PLL RF SAW SEL SET SEU SiGe TCXO VCA VCO Meaning Low Noise Amplifier Local Oscillator (down-converter) Noise Figure Oven Controlled Crystal Oscillator Printed Circuit Board Phase-Locked Loop Radio Frequency Surface Acoustic Wave Single Event Latch-up Single Event Transient Single Event Upset Silicon-Germanium (HBT) Temp. Compensated Crystal Oscillator Voltage Controlled Amplifier Voltage Control Oscillator Ordering Information Part SY1007R SY1007S Description GNSS receiver RF front-end IC, rad-hard. GNSS receiver RF front-end IC, space qualified, ESCC9000. Package Ceramic BGA 36 balls Ceramic BGA 36 balls Temperature −55 to +125◦ C Pack Tray RoHS No −55 to +125◦ C Tray No Related Products Part SY1008 SY1017C Daisy-Chain Description GNSS receiver RF front-end IC. AD/DA-converter/interface IC. Daisy-chain CBGA package. Comments Higher integration level, no external LO inductors. 3-bit I/Q AD-converter, 8-bit DA-converter (AGC). To develop and validate the soldering process. Via della Posta 10B 6934 Bioggio Switzerland Phone +41 91 220 1100 Fax +41 91 220 1101 http://www.saphyrion.ch DISCLAIMER SAPHYRION PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR IN APPLICATIONS WHICH INVOLVE POTENTIAL RISK OF DEATH, PERSONAL INJURY OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE IN CASE OF FAILURE OR MALFUNCTION OF THE PRODUCT. IN CASES WHERE EXTREMELY HIGH RELIABILITY IS REQUIRED (SUCH AS USE IN NUCLEAR POWER CONTROL, AEROSPACE AND AVIATION, TRAFFIC EQUIPMENT, MEDICAL EQUIPMENT, AND SAFETY EQUIPMENT), SAFETY SHOULD BE ENSURED BY USING SEMICONDUCTOR DEVICES THAT FEATURE ASSURED SAFETY OR BY MEANS OF USERS’ FAIL-SAFE PRECAUTIONS OR OTHER ARRANGEMENT. IN NO EVENT SHALL SAPHYRION BE LIABLE FOR ANY DAMAGES THAT MAY RESULT FROM AN ACCIDENT OR ANY OTHER CAUSE DURING OPERATION OF THE USER’S UNITS ACCORDING TO THE DATASHEET(S). 24 Saphyrion Sagl Rev. 1.4, January 31, 2014