1534 IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. 43, NO. 7, JULY 2008 A CMOS 5 nV= Hz 74-dB-Gain-Range 82-dB-DR Multistandard Baseband Chain for Bluetooth, UMTS, and WLAN Stefano D’Amico, Andrea Baschirotto, Senior Member, IEEE, Marcello De Matteis, Nicola Ghittori, Andrea Vigna, and Piero Malcovati, Senior Member, IEEE Abstract—An analog baseband chain for a multistandard (Bluetooth, WCDMA/UMTS, and WLAN) reconfigurable receiver in a 0.13 m CMOS occupying 1.65 mm2 is presented. The circuit consits of an open-loop programmable-gain amplifier (PGA1), an Activelow-pass filter (LPF), and a closed-loop programmable-gain amplifier (PGA2). The chain gain can be 68 dB, while the input-referred programmed in the range 6 noise (IRN) is 5 nV Hz. A dynamic range (DR) larger than 82 dB is achieved for a 1% total harmonic distortion (THD). The current consumption is minimized and adjusted for the different operation conditions, down to 11 mA for the full chain. Index Terms—Analog circuits, receivers, reconfigurable architectures. I. INTRODUCTION T HE implementation of an integrated multistandard transceiver, that is competitive with solutions based on parallel and separate devices for the different standards, must take into account various issues. First of all, both silicon area and static power consumption must be minimized, thus requiring the maximum possible hardware sharing among the transceivers for the different standards [1]–[3]. The challenges in designing the analog baseband section of such a reconfigurable receiver are mainly related to the significant difference in the standard specifications in terms of channel bandwidth, DC-gain ( ), noise, resolution, and linearity. The approach here adopted is to adjust the baseband circuit performance, including the power consumption, through a digital control (8 bit register for the full baseband chain) according to the standard in use. This solution allows us to re-use all the circuitry, adjusting the biasing conManuscript received November 12, 2007; revised February 15, 2008. This work was supported in part by the Italian National Program FIRB under Contract RBNE01F582. S. D’Amico and M. De Matteis are with the Department of Innovation Engineering, University of Salento, 73100 Lecce, Italy (e-mail: stefano.damico@unile.it; marcello.dematteis@unile.it). A. Baschirotto was with the Department of Innovation Engineering, University of Salento, Lecce, Italy. He is now with the University of Milano-Bicocca, Italy (e-mail: andrea.baschirotto@unimib.it). N. Ghittori was with the Department of Electrical Engineering, University of Pavia, Pavia, Italy. He is now with Marvell, Pavia, Italy (e-mail: nicolag@marvell.com). A. Vigna was with the Department of Electrical Engineering, University of Pavia, Pavia, Italy. He is now with Maxim, Milano, Italy (e-mail: av@design. mxim.com). P. Malcovati is with the Department of Electrical Engineering, University of Pavia, 27100 Pavia, Italy (e-mail: piero.malcovati@unipv.it). Digital Object Identifier 10.1109/JSSC.2008.922378 ditions of the active building blocks, and, eventually, turning on/off some stages. The paper is organized as follows. The baseband chain architecture and specifications are presented in Section II. Then, Section III describes in detail the analog baseband channel. The solution adopted for the first programmable gain amplifier of the chain (PGA1) is explained, focusing on input-referred noise (IRN) and frequency response characteristics. Then, we present the fourth-order low-pass filter (LPF) used in the chain, which is based on biquadratic cells realized with the Active topology. The last part of Section II is dedicated to the second programmable gain amplifier (PGA2) description, where the programmable gain is implemented by using a typical closedloop topology, while avoiding linearity problems and frequency response degradation. Finally, Section III is dedicated to the measurement results of the baseband chain, in terms of frequency response for each standard, linearity performance (IIP3) and output noise spectral density. II. BASEBAND CHAIN ARCHITECTURE Fig. 1 shows the overall receiver [4] architecture, based on a fully-differential structure. The circuit includes two RF 1.2 V with sections, one for UMTS and Bluetooth ( common-mode voltage at 0.6 V) and one for WLAN and Blue2.5 V with common-mode voltage at 1.25 V). tooth ( These two paths are connected through a multiplexer (MUX) at the input of two identical baseband chains (for the I and Q components). One standard at time can be processed by the proposed system, but the overall reconfigurable terminal will include two instances of the system, in order to allow the concurrent use of any combination of two standards. In the design considered in this paper, we realized the baseband chain using two PGAs and one LPF. An extended system study is reported in [3]. Each standard presents its own requirements in terms of bandwidth, DC-gain, noise and linearity. Here the main design strategies are summarized. The reconfigurable baseband chain requirements, have been obtained by considering the worst conditions of operation. For instance, for the noise performance and the maximum DC-gain requirement, the most critical standard is UMTS, with a required IRN of 5 nV Hz. Since this value is less than the maximum allowed for the other two standards [3], the UMTS noise requirement has been taken as specification for the overall baseband chain. 0018-9200/$25.00 © 2008 IEEE D’AMICO et al.: CMOS 5 nV Hz 74-dB-GAIN-RANGE 82-dB-DR MULTISTANDARD BASEBAND CHAIN FOR BLUETOOTH, UMTS, AND WLAN 1535 Fig. 1. Overall receiver architecture. TABLE I RECONFIGURABLE BASEBAND CHAIN MAIN REQUIREMENTS TABLE II DC-GAIN VERSUS BITS CONFIGURATION Fig. 2. PGA1 circuit. A. Programmable Gain Amplifier (PGA1) According to the noise performance, the baseband chain results over-designed for Bluetooth and WLAN operation modes. The power consumption is not optimized in these cases. This is the price to pay for reusing blocks in reconfigurable receivers. Otherwise, a number of circuit and architecture design solutions are adopted to reduce the overall power consumption. Moreover, a large chip area saving is obtained by sharing building blocks between the different operation modes. Bluetooth, UMTS and WLAN require 1 MHz, 2 MHz and 10 MHz of bandwidth, respectively. The bandwidth is selected through the LPF that presents a selectable cut-off frequency, according to the operation mode. The following strategy has been adopted for the DC-gain control. The LPF features a fixed DC-gain (4 dB) because in the adopted circuit solution, the DC-gain and the frequency control are not orthogonal. Therefore, by keeping the LPF DC-gain constant while programming the cut-off frequency, the circuit complexity is simplified. Otherwise the overall DC-gain of the baseband chain is determined by the two PGAs. The first PGA has wide gain steps (see Table II), while the second PGA features small gain steps (2.5 dB), that allow a fine gain control. Table I summarizes the baseband chain requirements. III. ANALOG BASEBAND CHANNEL The proposed baseband chain, as already mentioned, consists of two PGAs and one LPF (PGA1/LPF/PGA2, in Fig. 1). These different blocks will be discussed in the next subsections. The basic schematic of the PGA1 is reported in Fig. 2. A resistively-degenerated and resistively-loaded differential stage (whose DC-gain is fixed by the resistive ratio) is used [5]–[7]. For small input signals, the required large gain is achieved by , which accordingly minimizing the degeneration resistance reduces the IRN, while the load resistance , is maximized. For high gain mode, the PGA1 suffers for the out-of-band linearity. In fact, the intermodulation tone is amplified by the PGA1, and it can lead to the saturation of the overall baseband chain. In order to prevent this problem, the PGA1 bandwidth , the is reduced for high gain mode. In fact, by maximizing and , is pushed at lower frequency dominant pole due to for higher gain. As a consequence, the out-of-band tones are partially suppressed, and the intermodulation tone is attenuated. On the other hand, for large input signals, the required low gain is achieved by maximizing the degeneration resistance, which also increases the linear range. An output buffer adjusts the common-mode voltage and drives the following low-impedance load. The input stage follower guarantees large in-band linearity due to its large loop-gain. This circuit consists of a – converter (input opamps, & , and ), a resistive load ( ) and an output level shifter ( & ). This structure satisfies more efficiently the target specifications (input DC-level, noise, bandwidth, and power consumption) than using a classic structure. Moreover, the proposed PGA1 is able opampto work with 0.6 V and 1.25 V input common-mode level coming out from the RF part which is selected according to the & operate in source follower operation mode. Transistor 1536 IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. 43, NO. 7, JULY 2008 Fig. 5. Active G -RC cell. tors are connected (by means of a digital control) to synthesize the desired and values. and values are programmed through bits b0, b1 The and b2 which act on the switches realized with transistors M9, M10 and M11. When these switches are on, the corresponding resistors are connected in parallel, while, when they are off, the corresponding resistors are disconnected. The DC-gain map as a function of the bit configurations are reported in Table II. The switches are placed on the symmetry axis of the resistor array for two main reasons. Firstly, they do not add parasitic capacitances on the input transistors sources and drains nodes, which are the most critical for the overall PGA1 transfer function. Moreover, they are more linear due to the reduced signal swing across them. and The IRN of the PGA1 depends critically on the values and on the single-ended input stage opamp, as indicated in the following equation: Fig. 3. Input opamp. (2) Fig. 4. Gain control circuit. configuration; the differential input voltage is copied over the series impedance of the two nonlinear (of & ) and the linear degentransconductance . The linearity is improved by the eration resistors closed-loop gain. The additional opamp, shown in Fig. 3, uses a single differential pair with active load for large bandwidth and low noise level. This input stage single-ended opamp allows maximizing the follower loop-gain avoiding gain losses due to the body effect. Indeed the PGA1 DC-gain ( ) is approximated by the following equation: (1) where is the additional opamp DC-gain, and is the transconductance of the input stage M1&M2. The PGA1 gain depends on the degeneration ( ) and load ( ) resistances. In order to program the gain , these resistances have to be adjusted. Both of them have been implemented as a resistors array (as shown in Fig. 4), and a number of resis- 5 nV Hz (this contriThe PGA1 exhibits a low bution is dominant due to the large baseband chain gain, up to 68 dB), a large input common-mode range (the input bias voltage is 0.6 V for the cellular RF-front-end, while it is 1.25 V for the WLAN RF front-end), a large bandwidth (to avoid in-band signal attenuation) and a large gain programmability dB dB for WLAN, and dB 29 dB for the other ( standards). B. Low-Pass Filter (LPF) The fourth-order channel LPF is realized with the cascade biquadratic cells [8]–[13]. In Fig. 5 the of two Activeschematic of the single biquadratic cell is presented. The opamp has a single-pole transfer function (in the frebiquadratic cell quency range of interest). In the Active the opamp is used as open loop integrator, in order to synthesize a complex pole pair. The opamp transfer function can be written as (3) and are the opamp first-pole angular frequency where and the DC-gain, respectively. The opamp uses a two-stage Miller topology, as shown in Fig. 6. The equivalent circuit of the entire cell is represented in Fig. 7. It consists of an input stage (the input transconductance and the load resistance), an output stage (the output transcon- D’AMICO et al.: CMOS 5 nV Hz 74-dB-GAIN-RANGE 82-dB-DR MULTISTANDARD BASEBAND CHAIN FOR BLUETOOTH, UMTS, AND WLAN 1537 Fig. 6. Miller opamp schematic. Fig. 7. Equivalent circuit of the active G -RC cell. ductance and the load resistance), and a Miller compensation and ). network (resistor and capacitor In addition the load contribution ( and ) of the other circuits connected to the cell is shown. In Fig. 7 an adjusting . The adjusting circuit effect circuit [8] sets is to change the dependence of the filter frequency response on the MOS device parameters into a dependence on the passive component values ( , , , ). In this way the biquadratic cell can be reconfigured by the external digital circuitry. The adjusting circuit forces the operational amplifier frequency response to track its time constant with the passive components ( and ). Therefore, the biquadratic cell cut-off frequency depends directly on the passive components values, with , a tuning resistance and capacitance. Matching circuit based on the time constant adjusting can be used in order to compensate the frequency response variations due to the technological spread, temperature and aging. The Accell exhibits the following key features. tive• Low power consumption (a key issue for portable terminals): one operational amplifier is used to synthesize a second-order transfer function. In addition the operational amplifier unity-gain-bandwidth, , is comparable to the filter pole . This reduces its power consumption with respect to other single opamp closed-loop structures (Acor MOSFET-C), where a larger than tiveis used, with a higher power consumption; • High linearity: a very large linear range is achieved thanks to the filter closed-loop structure. Fig. 8 shows the frequency response at the out-of-band signals are first fillow-pass filter at the input. tered by the very linear G RC Fig. 8. Activebiquad cell frequency response at the output node and at the opamp input node. This gives a large out-of-band IP3, which results useful in telecom systems where the higher amplitude of out-ofband blockers requires a large out-of-band linearity. Furinput net filtering is very thermore, in this design, the cell is placed after important because the Active the PGA1 stage, where the DC-gain can be 29 dB and the out-of-band frequencies close maximum in-band frequency. For reference, Fig. 9 shows the UMTS input spectrum at the antenna, which is down-converted and amplified by the RF front-end, and then it is present (shifted in frequency around DC) at the PGA1 input. Out-of band blockers larger than 60 dB w.r.t. the signal have to be processed by baseband chain [14], [15]. Out-of band blockers are partially smoothed by the PGA1 thanks to its pole, then they are better suppressed by the filter. • Frequency response accuracy: The adjusting circuit makes the opamp frequency response dependent on the passive component values ( and ) spread, which is the only 1538 IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. 43, NO. 7, JULY 2008 Fig. 9. Detailed block diagram of the PGA2. Fig. 10. UMTS signal spectrum. spread to be compensated and this is done by the tuning system. This makes this approach completely different from the previous approach [16], [9], where the opamp frequency response is taken into account “as it is” to synthesize the desired transfer function. In this previous approach, the filter transfer function strongly suffers from the opamp frequency response sensitivity to technology, component spreading, and temperature. This is not the filters, whose frequency response case of the Activeis completely under the tuning system control. The cell cut-off frequency can be programmed among three possible values, according to the selected standard: • 1 MHz for Bluetooth; • 2.2 MHz for UMTS; 4 dB. • 11 MHz for WLAN with For the lower bandwidth cases the power consumption is reduced by controlling the input stage device sizes and their current levels. For all the standards, the grounded resistors are used to control also the common-mode voltage. C. Programmable Gain Amplifier (PGA2) After the PGA1 and the LPF, the quite large PGA2 input signal amplitude requires more linearity than noise performance [6], [7]. A closed-loop architecture is therefore used. Two gainstages are adopted as a tradeoff between the number of stages (increasing complexity and noise) and the gain-per-stage (increasing the power consumption), as shown in the detailed block diagram reported in Fig. 10 [17]. The opamps present, the same structure reported in Fig. 6. In the used structure, the signal current does not flow through , thus avoiding the nonlinear resistance of the switches linearity and frequency response accuracy degradation. In fact the switches are connected between the opamp input node, and resiswhere ideally there is no signal swing, and the flows through without tances. So the signal current flowing in the switches, so that the input signal bypasses the switches. Furthermore, the finite on/off switch resistance does and values. This technique is not affect the nominal largely used at low frequency, in audio applications. Anyway, the technology improvements allow us to adjust it in order to work at the operation frequency of the modern telecom receivers. The two stages are slightly different. The first and the second gain stage have a gain-programmability range of dB dB and dB dB , respectively, with 2.5 dB step each. The second stage also implements a first-order 15 MHz low-pass transfer function. A feed-back capacitor in has been inserted in the second stage. The parallel with capacitor is adjusted according to the selected gain in order to maintain the cut-off frequency constant with gain programmability [17]. This filtering action allows the stage to be stable also for low gain values, i.e., when the loop-gain is high, and the phase margin is reduced. For this reason, for gain values up to 10 dB it is used alone, while the first stage is bypassed and turned off (saving power). For larger gain values, the first stage is turned on and realizes a minimum gain of 10 dB. This is because, since it is not implementing a low-pass transfer function, it would be unstable for low gain values. Finally, as shown in Fig. 10, re- D’AMICO et al.: CMOS 5 nV Hz 74-dB-GAIN-RANGE 82-dB-DR MULTISTANDARD BASEBAND CHAIN FOR BLUETOOTH, UMTS, AND WLAN 1539 Fig. 12. Programmable frequency response. Fig. 11. Chip photograph. sistors, , have been included. These resistors are driven by an analog off chip voltage, which is chosen in order to compen) in order not to affect the sate the offset. They are large (20 noise performance. The current of each stage, equal to 2 mA, is comparable with state-of-the-art performance [17]. A tuning circuit, compensating technology, temperature and worst-case effects adjusts the frequency response of the full baseband chain. A 4 bit word is passed both to LPF and PGA2, guaranteeing a cut-off frequency error lower than 5%. The tuning circuit is reported in [8]. Fig. 13. In-band and out-of-band linearity performance (UMTS setting). IV. EXPERIMENTAL RESULTS The baseband receiver chain has been realized in a 0.13 m CMOS technology using only 2.5 V 0.13 m devices with double-oxide. The chip photo is shown in Fig. 11. It is embedded in a fully reconfigurable receiver and occupies a 1.65 mm die size. The resistors and the capacitors are designed as multiple of a minimum common size, in order to have a better matching. The baseband chain has been successfully tested in standalone configuration in all the required operation conditions. The frequency response for different gain levels and cut-off frequencies is shown in Fig. 12. For the Bluetooth case a filter bandwidth larger than the standard requirement is implemented. For the system design, the WLAN gain is up to 39 dB, while for the UMTS and Bluetooth the gain is up to 68 dB. The reference resistance for the reported data expressed in dBm is 50 . The linearity performance has been evaluated in terms of input intermodulation intercept point IIP3 for different cases. In the UMTS case the performance is reported in Fig. 13: in-band (tones at 700 kHz and 800 kHz) IIP3 21 dBm (for Fig. 14. 1 dB compression point (WLAN setting). 4 dB) and out-of-band (tones at 10 MHz and 19 MHz) 41 dB). OIP3 50.5 dBm (for In the WLAN and Bluetooth cases, the two tones for the IIP3 test are at 3 MHz, 4 MHz and 300 kHz, 400 kHz, respectively. Also in this case, the obtained IIP3 is 21 dBm. The in-band linearity performance are quite close for all operation modes. Fig. 14 shows the input 1 dB compression point equal to 4 dB). 1.3 dBm ( The noise level is dominated by the PGA1 performance, 5 nV Hz noise floor, as shown in which exhibits an IRN Fig. 15. For and WLAN setting, the baseband chain features a total harmonic distortion (THD) of 40 dB for a 4 dBm input signal, which gives a dynamic range (DR) of 82 dB. The current consumption is optimized according to the operation condition. It goes from 11 mA (UMTS/Bluetooth mode, 1540 IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. 43, NO. 7, JULY 2008 TABLE III PERFORMANCE SUMMARY [2] R. Bagheri, A. Mirzaei, S. Chehrazi 1, M. Heidari, M. Lee, M. Mikhemar, W. Tang, and A. Abidi, “An 800MHz to 5GHz software-defined radio receiver in 90nm CMOS,” in IEEE ISSCC Dig. Tech. Papers, 2006, pp. 480–481. [3] F. Agnelli, G. Albasini, I. Bietti, A. Gnudi, A. Lacaita, D. Manstretta, R. Rovatti, E. Sacchi, P. Savazzi, F. Svelto, E. Temporiti, S. Vitali, and R. Castello, “Wireless multi-standard terminals: System analysis and design of a reconfigurable RF front-end,” IEEE Circuits Syst. Mag., vol. 6, no. 1, pp. 38–59, 1st Quarter, 2006. [4] N. Ghittori, A. Vigna, P. Malcovati, S. D’Amico, and A. Baschirotto, “Analog baseband channel for GSM/UMTS/WLAN/Bluetooth reconfigurable multistandard terminals,” in Proc. ISCAS’06, May 2006, pp. 4301–4304. [5] S. D’Amico, M. De Matteis, and A. Baschirotto, “A 6.4 mW, 4.9 nV= Hz), 24 dBm IIP3 VGA for a multi-standard (WLAN, UMTS, GSM, and Bluetooth) receiver,” in Proc. ESSCIRC’06, Sep. 2006, pp. 82–85. [6] P. Pessl, R. Gaggl, J. Hohl, D. Giotta, and J. Hauptmann, “A fourchannel ADSL2+ analog front-end for CO applications with 75 mW per channel, built in 0.13-m CMOS,” IEEE J. Solid-State Circuits, vol. 39, no. 12, pp. 2371–2378, Dec. 2004. [7] C.-P. Wu and H.-W. Tsao, “A 110-MHz 84-dB CMOS programmable gain amplifier with integrated RSSI function,” IEEE J. Solid-State Circuits, vol. 40, no. 6, pp. 1249–1258, Jun. 2005. [8] S. D’Amico, V. Giannini, and A. Baschirotto, “A 4th-order active-G -RC reconfigurable (UMTS/WLAN) filter,” IEEE J. Solid-State Circuits, vol. 41, no. 7, pp. 1630–1637, Jul. 2006. [9] S. D’Amico, A. Baschirotto, and A. Gola, “Continuous-time filter,” U.S. patent 7,026,856, Apr. 11, 2006. [10] B. Guthrie, J. Hughes, T. Sayers, and A. Spencer, “A CMOS gyrator low-IF filter for a dual-mode Bluetooth/ZigBee transceiver,” IEEE J. Solid-State Circuits, vol. 40, no. 9, pp. 281–294, Sep. 2005. [11] S. D’Amico and A. Baschirotto, “Active G -RC continuous-time biquadratic cells,” Analog Integr. Circuits Signal Process., vol. 45, no. 3, pp. 281–294, Nov. 2005. [12] H. A. Alzaher and M. K. Alghamdi, “A CMOS bandpass filter for low-IF Bluetooth receivers,” IEEE Trans. Circuits Syst. I, vol. 53, no. 8, pp. 1636–1647, Aug. 2006. [13] K. R. Rao and S. Srinivasan, “A bandpass filter using the operational amplifier pole,” IEEE J. Solid-State Circuits, vol. 8, no. 3, pp. 245–246, Jun. 1973. [14] D. Manstretta, R. Castello, F. Gatta, P. Rossi, and F. Svelto, “A 0.18 m CMOS direct- conversion receiver front-end for UMTS,” in IEEE ISSCC Dig. Tech. Papers, 2002, pp. 240–463. p Fig. 15. Input-referred noise spectrum. 21.5 dB DC-gain) up to 22 mA (WLAN mode 39 dB DC-gain). Table III summarizes the performance of the circuit. V. CONCLUSION In this paper, we presented a complete analog baseband channel for a multistandard reconfigurable receiver supporting UMTS, WLAN and Bluetooth. The channel consists of three functional blocks: a programmable gain amplifier, a low-pass filter, and a last stage again providing programmable gain. In the UMTS mode the maximum achievable gain is 68 dB, while in the WLAN mode it is reduced to 39 dB. Measurements on the implemented baseband section validate the proposed design, as the main receiver tests imposed by the standards are fulfilled with a maximum total current consumption limited to 22 mA (WLAN mode, 38 dB DC-gain). REFERENCES [1] A. Baschirotto, R. Castello, F. Campi, G. Cesura, M. Toma, R. Guerrieri, A. Lodi, L. Lavagno, and P. Malcovati, “Baseband analog front-end and digital back-end for reconfigurable multi-standard terminals,” IEEE Circuits Syst. Mag., vol. 6, no. 1, pp. 8–28, 1st Quarter, 2006. D’AMICO et al.: CMOS 5 nV Hz 74-dB-GAIN-RANGE 82-dB-DR MULTISTANDARD BASEBAND CHAIN FOR BLUETOOTH, UMTS, AND WLAN [15] K. R. Rao, J. Wilson, and M. Ismail, “A CMOS RF front-end for a multistandard WLAN receiver,” IEEE Microw. Wireless Compon. Lett., vol. 15, no. 5, pp. 321–323, May 2005. [16] T. Tsukutani et al., “Current-mode biquad without external passive elements,” Electron. Lett., pp. 197–198, Feb. 1996. [17] N. Ghittori, A. Vigna, P. Malcovati, S. D’Amico, and A. Baschirotto, “Design of a low-power variable gain amplifier for reconfigurable wireless receivers,” in Proc. ICECS, 2005, pp. 394–397. Marcello De Matteis received the degree in electronic engineering from the Politecnico di Milano, Italy, in 2004. In 2008, he received the Ph.D. degree in information engineering from the University of Salento, Lecce, Italy. He is currently with the Department of Innovation Engineering, University of Salento, Italy, as a Postdoctoral Researcher. His research topic is the design of low-power analog filters and amplifiers for telecommunication receivers baseband chain. Stefano D’Amico received the degree in electrical engineering from the Politecnico di Bari, Italy, in 2001. In 2005, he received the Ph.D. degree from the University of Salento, Italy. He is currently with the Department of Innovation Engineering, University of Salento, as an Assistant Professor. He has authored or co-authored more than 12 papers in international journals, more than 60 presentations at international conferences (with published proceedings), two book chapters, and three industrial patents. His research topics are low-power baseband analog circuits for sensors interface and telecommunications. Dr. D’Amico was the secretariat of the IEEE PRIME 2006 Conference. He is associate editor for Europe of the Journal of Circuits, Systems, and Computers. Andrea Baschirotto (M’95–SM’01) was born in 1965 in Legnago (Verona), Italy. He graduated in electronic engineering (summa cum laude) from the University of Pavia, Pavia, Italy, in 1989. In 1994, he received the Ph.D. degree in electrical engineering from the University of Pavia. In 1994, he joined the Department of Electronics, University of Pavia, as a Researcher (Assistant Professor). In 1998, he joined University of Lecce, Italy, as an Associate Professor. In 2007, he joined the University of Milano-Bicocca, Italy, as an Associate Professor. About his research activity, he founded and he is leading the Microelectronics Group at University of Lecce, which is collaborating with several companies and research institutions (IMEC, Infineon, University of Pavia, RFDomus, STMicroelectronics, etc.). His main research interests are in the design of CMOS mixed analog/digital integrated circuits, in particular for lowpower and/or high-speed signal processing. He has participated in several research collaborations, also funded by National and European projects. He is and has been responsible for some National and Regional projects for the design of ASICs. Since 1989, he has collaborated with several companies on the design of mixed-signal ASICs, including STMicroelectronics, Mikron, ACCO, ITC-IRST, IMEC, RFDomus (he was in its Advisory Board), etc. He has authored or co-authored more than 190 papers in international journals and presentations at international conferences, six book chapters, and holds 25 U.S. patents. In addition, he has co-authored more than 120 papers within research collaborations on high-energy physics experiments. He has a long-term experience in microelectronics in teaching, researching, and industrial designing. He has been teaching regular academic courses since 1997. He organized the full educational courses for electronics engineering (Bachelor, Master, and Ph.D.) at the University of Lecce. He has given industrial courses since 1996 (in Bosch, STMicroelectronics, ITC-IRST, Conexant, Mikron, etc.). He is a speaker at the MEAD Summer courses held at EPFL (Lausanne, Switzerland). He has given short courses or tutorial at the most important conferences (ISSCC, ISCAS, PRIME). Dr. Baschirotto was an Associate Editor for IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS–PART II for the period 2000–2003, and of TRANSACTIONS ON CIRCUITS AND SYSTEMS–PART I for the period 2004–2005. He was the Guest Editor for the IEEE JOURNAL OF SOLID-STATE CIRCUITS special issue on ESSCIRC 2003. He was the Technical Program Committee Chairman for ESSCIRC 2002, and he was the General Chair of PRIME2006. He is a member of the Technical Program Committee of several international conferences, including ISSCC, ESSCIRC, and DATE. Since 2008, he has been the Secretary of the European Committee of ISSCC. He is the General Coordinator of a National PRIN Project on reconfigurable high-dynamic range gas sensor systems. 1541 Nicola Ghittori received the Laurea degree (summa cum laude) and the Ph.D. degree in electronic engineering from the University of Pavia, Italy, in 2002 and 2006, respectively. During his Ph.D., he worked on CMOS analog circuits for wireless transceivers and analysis of package and substrate crosstalk in mixed-signal integrated circuits. He is currently with Marvell Semiconductor, Pavia, Italy. Andrea Vigna was born in Broni, Italy, in 1977. He received the Laurea degree (summa cum laude) and the Ph.D. degree in electrical engineering and computer science from the University of Pavia, Italy, in 2002 and 2006, respectively. During his Ph.D., he worked on analog integrated circuits for wireless transceivers, in CMOS technologies, with particular focus on the analysis and design of D/A conversion systems for multistandard transmitters. He is currently with Maxim Integrated Products (System and Power Management Business Unit), Pavia, Italy. Piero Malcovati (M’95–SM’05) was born in Milano, Italy, in 1968. He received the Laurea degree (summa cum laude) in electronic engineering from the University of Pavia, Italy, in 1991. In 1992, he joined the Physical Electronics Laboratory (PEL) at the Federal Institute of Technology in Zurich (ETH Zurich), Switzerland, as a Ph.D. candidate. He received the Ph.D. degree in electrical engineering from ETH Zurich in 1996. From 1996 to 2001, he was an Assistant Professor in the Department of Electrical Engineering, University of Pavia. Since 2002, he has been an Associate Professor of electrical measurements in the same institution. His research activities are focused on microsensor interface circuits and high performance data converters. He has authored or co-authored more than 40 papers in international journals, more than 150 presentations at international conferences (with published proceedings), seven book chapters, and five industrial patents. Dr. Malcovati was a co-recipient of the ESSCIRC 2007 Best Paper Award. He was guest editor for the Journal of Analog Integrated Circuits and Signal Processing for the special issue on IEEE ICECS 1999. He served as Special Session Chairman for the IEEE ICECS 2001 Conference, as Secretary of the Technical Program Committee for the ESSCIRC 2002 Conference and as Technical Program Chairman of the IEEE PRIME 2006 Conference. He was and still is a member of the Scientific Committees for several international conferences, including ESSCIRC, DATE, and PRIME. He is the regional editor for Europe of the Journal of Circuits, Systems, and Computers, as well as Associate Editor for the IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II.