DEMO MANUAL DC1245A
LTM4616
Dual 2.7VIN(MIN), 8A Step-Down
µModule Regulator
Description
Demonstration circuit 1245A features the LTM®4616, the
high efficiency, high density, dual output switch mode
power module. The rated load current is 8A for each channel, while derating is necessary for certain VIN, VOUT, and
thermal conditions. By applying a clock signal to the CLKIN
pin, the module’s switching frequency may be synchronized
from 0.75MHz to 2.25MHz. The same clock frequency is
available at the CLKOUT pin with the phase relationship
between CLKIN and CLKOUT determined by the PHMODE
pin. This feature can be used not only to reduce undesirable
PERFORMANCE SUMMARY
PARAMETER
frequency harmonics but also to parallel the two channels
of LTM4616 or even multiple LTM4616s and LTM4608s to
provide higher output currents. The LTM4616 data sheet
must be read in conjunction with this demo manual prior
to working on or modifying demo circuit DC1245A.
Design files for this circuit board are available at
http://www.linear.com/demo/DC1245A
L, LT, LTC, LTM, µModule, Linear Technology and the Linear logo are registered trademarks of
Linear Technology Corporation. All other trademarks are the property of their respective owners.
(TA = 25°C)
CONDITIONS
Input Voltage Range
VALUE
2.7V to 5.5V
Output Voltage VOUT1
VOUT2
VIN = 3.3V, IOUT1 = 8A
IOUT2 = 8A
1.8 ±2%
1.2 ±2%
Maximum Continuous Output Current
Derating Is Necessary for Certain VIN, VOUT, and Thermal
Conditions, See Data Sheet for Details
8ADC Each Channel
Default Operating Frequency
1.5MHz
Efficiency
VIN = 5V, VOUT1 = 1.8V, VOUT2 = 1.2V, 8A Per Channel
77.5%, See Figure 3 for More Information
Load Transient
VIN = 3.3V, VOUT1 =1.8V; VOUT2 = 1.2V
See Figures 4 and 5 for Details
Board Photo
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DEMO MANUAL DC1245A
quick start procedure
Demonstration circuit 1245A is an easy way to evaluate
the performance of the LTM4616. Please refer to Figure 1
for proper measurement equipment setup and follow the
procedure below:
1.Place jumpers in the following positions for a typical
1.8VOUT and 1.2VOUT application:
PHMODE2
MARGINING2
RUN2
MARGINING1
2PH
NO
ON
NO
TRACK1
PHMODE1
MODE
RUN1
DISABLED
2PH
BURST
ON
2.With power off, connect the input power supply, load
and meters as shown in Figure 1. Preset the load to 0A
and VIN supply within the 2.7V to 5.5V operating range.
4.Once the proper output voltage is established, adjust
the load within the operating range and observe the
output voltage regulation, ripple voltage, efficiency and
other parameters. To measure input and output ripple,
please refer to Figure 2 for proper setup.
5.To synchronize channel 1 to an external clock, please
apply the desired clock signal to CLKIN and SGND1.
The external clock signal should have amplitude of at
least 2V but less than VIN.
6.VOUT1 can track another supply connected at TP20 as
determined by resistors R6 and R17. VOUT2 is set up
to track VOUT1 in a manner determined by resistors
R15 and R16. By default both resistor pairs have been
selected to support coincident tracking. Please refer to
Figure 6 for reference.
3.Turn on the power at the input. The output voltage at
VO1+ and VO1– should be 1.8V ±2% and the voltage
at VO2+ and VO2– should be 1.2V ±2%.
INPUT OR OUTPUT CAPACITOR
Figure 2. Proper Scope Probe Placement
for Measuring Input or Output Ripple
Overall Efficiency vs Load Current
95
VIN = 3.3V, VO1 = 1.8V, VO2 = 1.2V
90
85
EFFICIENCY (%)
80
75
VIN = 5V, VO1 = 1.8V, VO2 = 1.2V
70
65
60
55
50
45
40
35
0
2
6
4
8
10
LOAD CURRENT FOR EACH CHANNEL (A)
dc1245a F03
Figure 3. Measured Overall Supply Efficiency with Different VIN
Figure 1. Test Setup of DC1245A
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DEMO MANUAL DC1245A
quick start procedure
7.Channel 2 is set up to synchronize to the CLKOUT signal of channel 1. The default phase difference is 180°.
Please refer to data sheet for how to set up PHMODE1
and PHMODE2 for paralleling more than 2 channels.
dc1245a F05
VIN = 3.3V
VOUT =1.2V
CONTINUOUS CURRENT MODE (CCM)
2A TO 6A LOAD STEP
COUT = ×2 100µF CERAMIC (1210, X5R, 6.3V) +
22µF CERAMIC (0805, X5R, 6.3V)
CFF2 = 0pF
VOUT OVERSHOOT AND UNDERSHOOT = 128mV
dc1245a F04
VIN = 3.3V
VOUT =1.8V
CONTINUOUS CURRENT MODE (CCM)
2A TO 6A LOAD STEP
COUT = ×2 100µF CERAMIC (1210, X5R, 6.3V) +
22µF CERAMIC (0805, X5R, 6.3V)
CFF1 = 47pF
VOUT OVERSHOOT AND UNDERSHOOT = 172mV
Figure 5. Measured Load Transient Response for 1.2VOUT
(4A Step, 25% to 75%)
Figure 4. Measured Load Transient Response for 1.8VOUT
(4A Step, 25% to 75%)
Figure 6. Measured Tracking Performance of VOUT1 and VOUT2
(with 2A Load Current)
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DEMO MANUAL DC1245A
parts list
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
Required Circuit Components
1
4
CIN1, CIN2, CO13, CO23
Capacitor, X5R, 22µF, 6.3V, 20%, 1206
AVX, 12066D226MAT2A
2
1
CIN4
Capacitor, OS-CON, 150µF, 10V, E7 Size
Sanyo, 10SVPA150MAA
3
4
CO11, CO12, CO21, CO22
Capacitor, X5R, 100µF, 6.3V, 20%, 1210
AVX, 12106D107MAT2A
4
1
RSET1
Resistor, Chip, 4.99k, 1/16W, 1%, 0402
Vishay, CRCW04024K99FKED
5
1
RSET2
Resistor, Chip, 10k, 1/16W, 1%, 0402
Vishay, CRCW040210K0FKED
6
1
U1
IC LTM4616EV 144-Pin LGA
Linear Technology, LTM4616EV
Additional Demo Board Circuit Components
1
0
CO14, CO15, CO24, CO25 (OPT)
Capacitor, 1210-3743
2
2
R7, R5
Resistor, Chip, 100k, 1/16W, 5%, 0402
3
0
R9, R11, R19 (OPT)
Resistor, Chip, 0402
Vishay, CRCW0402100KJNED
4
0
CTHP1, CTHP2, C1, CFF2, CSP (OPT)
Capacitor, 0402
5
1
CFF1
Capacitor, C0G, 47pF, 50V, 10%, 0402
AVX, 04025A470KAT2A
6
1
R17
Resistor, Chip, 4.99k, 1/16W, 1%, 0402
Vishay, CRCW04024K99FKED
7
3
R15, R16, R6
Resistor, Chip, 10k, 1/16W, 1%, 0402
Vishay, CRCW040210K0FKED
8
1
R18
Resistor, Chip, 0, 1/16W, 0402
Vishay, CRCW04020000Z0ED
Hardware/Components (For Demo Board Only)
1
0
CIN3(OPT)
Capacitor, 1210-3743
2
5
JP1, JP2, JP3-JP5
2 × 3, 0.079 Double Row Header
Samtec, TMM103-02-L-D
3
3
JP6, JP7, JP9
Header 3-Pin 0.079 Single Row
Samtec, TMM103-02-L-S
4
8
JP1-JP7, JP9
Shunt, 0.079" Center
Samtec, 2SN-BK-G
5
15
TP1, TP2, TP7-TP10, TP12, TP14-TP18,
TP20-TP22
Testpoint, Turret, 0.094" Pbf
Mill-Max, 2501-2-00-80-00-00-07-0
6
2
TP6, TP3
Stud, Test Pin
PEM KFH-032-10
7
4
TP6, TP3
Nut, Brass Nuts #10-32
Any #10-32
8
2
TP6, TP3
Ring, Lug Ring #10
Keystone #10
9
2
TP6, TP3
Washer, Tin Plated Brass
Any #10
10
4
TP4, TP5, TP11, TP13
Jack Banana
Keystone, 575-4
11
4
(STAND-OFF)
Stand-Off, Nylon 0.50"
Keystone, 8833(SNAP ON)
dc1245afa
4
TP3
TP8
TP6
BURST
SVIN1
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
SGND1
CLKIN
TP22
TP21
TP20
3PH (PHASE)
4PH (PHASE)
2PH (PHASE)
2
6
4
6
3
5
10K
R6
R17
4.99K
CIN3
100uF
opt
ITHM2
ITH2
CIN1
22uF
6.3V
ON
OFF
2
SVIN1
C1
opt
RUN1
JP7
CFF1
47pF
ITHM2
RSET1
4.99K
R11 opt
opt
A11
VFB
F5
A7
F6
E8
A9
D8
F7
E7
A8
A10
A6
G11
MODE1
MGN1
BSEL1
PGOOD2
PGOOD1
SGND1
CLKIN1
RUN1
TRACK1
PHMODE1
FB1
CLKOUT1
ITHM1
CTHP1 F8
ITH1
opt.
CLK
R7
100K
R9
MODE
R5
100K
ITH2
VOUT1
TP16
TP15
CIN2
22uF
6.3V
SVIN1
SVIN2
IN LAYOUT, MANUALLY TIED ALL GND TOGETHER ON LAYER 2.
*DC1245A STILL USES THE OLD METHOD TO DISABLE MARGINING.
AN IMPROVED METHOD OF TYING THE MGN PIN TO A VOLTAGE DIVIDER
WITH 50k RESISTORS FROM VIN TO GROUND IS RECOMMENDED NOW.
ENABLED
2
SVIN1
JP6
TRACK1
2
1
JP4
PHMODE1
4
5
2
6
4
3
1
JP3
MODE
DISABLED
SVIN1
(CONTINUOUS) CON
TRACK
HI 1
150uF
10V
+ CIN4
JP1*
MARGINING1
TP12
TP10
NO 3
LOW 5
SVIN1
(PULSE SKIPPING) PS
VOUT1
PBS1
PGOOD2
PGOOD1
VIN-
GND
2.5V - 5.5V
VIN
1
3
VIN
1
3
F1
F2
F3
F4
E1
E2
E3
E4
D1
D2
C1
C2
VIN1
VIN1
VIN1
VIN1
VIN1
VIN1
VIN1
VIN1
VIN1
VIN1
VIN1
VIN1
B6
SW1
E5
SVIN1
H6
SW2
J1
J2
K1
K2
L1
L2
L3
L4
M1
M2
M3
M4
A1
A2
A3
A4
A5
A12
B1
B2
B3
B4
B5
B7
B8
B9
B10
B11
B12
C3
C4
C5
C6
C7
C8
C9
C10
C11
C12
D3
D4
D5
D6
D7
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
GND1
VIN2
VIN2
VIN2
VIN2
VIN2
VIN2
VIN2
VIN2
VIN2
VIN2
VIN2
VIN2
L5
SVIN2
FB2
CLKOUT2
ITHM2
ITH2
MODE2
MGN2
BSEL2
VOUT2
VOUT2
VOUT2
VOUT2
VOUT2
VOUT2
VOUT2
VOUT2
VOUT2
VOUT2
VOUT2
VOUT2
VOUT1
VOUT1
VOUT1
VOUT1
VOUT1
VOUT1
VOUT1
VOUT1
VOUT1
VOUT1
VOUT1
VOUT1
SGND2
CLKIN2
PLLFLTR1
PLLFLTR2
RUN2
TRACK2
PHMODE2
LTM4616EV
U1
M5
G7
E6
L6
M6
L8
G9
K8
M7
L7
M8
G8
G10
G6
K9
K10
K11
K12
L9
L10
L11
L12
M9
M10
M11
M12
D9
D10
D11
D12
E9
E10
E11
E12
F9
F10
F11
F12
CLK
ITHM2
MODE
ITH2
CSP
opt
CTHP2
opt.
APPROVED
Friday, February 15, 2008
3/7/07
M. Xie
6
4
2
VOUT1
VO1+
GND1
VO2+
VO1-
TP13
HI
VFB
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900
Fax: (408)434-0507
TP18
TP17
CLKOUT
SVIN2 VOUT2
PBS2
VO2-
GND2
VOUT2
TP11
1.2V @ 8A MAX
TP9
TP7
TP5
1.8V @ 8A MAX
TP4
TP14
NO
3
5 LOW
1
TECHNOLOGY
3PH (PHASE)
4PH (PHASE)
FILENAME:
CAGE CODE
SCALE:
SIZE
CO25
opt
6.3V
CO15
opt
6.3V
JP2*
MARGINING2
2PH (PHASE)
CO24
opt
6.3V
CO14
opt
6.3V
TP2
DWG NO
SHEET
DC1245A
1
OF
LTM4616EV
Dual 8A High Density Step-Down Power Module
5
TITLE
3
6
DATE
1
4
3/7/07
CHECKED
opt
VOUT2
SVIN2
R19
2
J. Wu
ENGINEER
CO23
22uF
6.3V
SVIN2
JP5
PHMODE2
APPROVALS
DRAWN
JP9
RUN2
ON
opt
VFB
PFB2
PFB1
CFF2
OFF
SVIN2
2
CO22
100uF
6.3V
CO21
100uF
6.3V
VOUT2
CO13
22uF
6.3V
VOUT1
10.0K 1%
CO12
100uF
6.3V
CO11
100uF
6.3V
RSET2
CONTRACT NO.
R16
10.0K
1%
R15
10.0K
1%
VOUT1
R18 0
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
CUSTOMER NOTICE
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
GND2
G1
G2
G3
G4
G5
G12
H1
H2
H3
H4
H5
H7
H8
H9
H10
H11
H12
J3
J4
J5
J6
J7
J8
J9
J10
J11
J12
K3
K4
K5
K6
K7
TP1
1
3
VIN+
A
1
REV
DEMO MANUAL DC1245A
Schematic Diagram
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DEMO MANUAL DC1245A
DEMONSTRATION BOARD IMPORTANT NOTICE
Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions:
This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT
OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use. As such, the DEMO BOARD herein may not be complete
in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety
measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union
directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations.
If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual the kit may be returned within 30 days from the date
of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY THE SELLER TO BUYER AND IS IN LIEU
OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS
FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR
ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.
The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user releases LTC from all claims
arising from the handling or use of the goods. Due to the open construction of the product, it is the user’s responsibility to take any and all
appropriate precautions with regard to electrostatic discharge. Also be aware that the products herein may not be regulatory compliant or
agency certified (FCC, UL, CE, etc.).
No License is granted under any patent right or other intellectual property whatsoever. LTC assumes no liability for applications assistance,
customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind.
LTC currently services a variety of customers for products around the world, and therefore this transaction is not exclusive.
Please read the DEMO BOARD manual prior to handling the product. Persons handling this product must have electronics training and
observe good laboratory practice standards. Common sense is encouraged.
This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LTC application engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation
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6
Linear Technology Corporation
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●
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