Linear Technology DC1498A Quick setup guide

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DEMO MANUAL DC1498A
Description
LTM4620EV
High Efficiency, Dual 13A Step-Down
Power µModule Regulator
DC1498A features the LTM
®
4620EV, the high efficiency,
high density, dual 13A, switch mode step-down power
module regulator. The input voltage is from 4.5V to 16V.
The output voltage is programmable from 0.6V to 2.5V.
DC1498A can deliver nominal 12A output current and
up to 13A maximum in each channel. As explained in
the data sheet, output current derating is necessary for
certain VIN, VOUT, and thermal conditions. The board
operates in continuous conduction mode in heavy load
conditions. For high efficiency at low load currents, the
MODE jumper (JP1) selects pulse-skipping mode fornoise
sensitive applications or Burst-Mode
®
operation in less
noise sensitive applications.Two outputs can be connected
in parallel for a single 26A output solution with optional
jumper resistors. The board allows the user to program
how its output ramps up and down through the TRACK/SS
pin. The output can be set up to either coincidentally or
ratiometrically track with another supply’s output. Remote
output voltage sensing is available for improved output
voltage regulation at the load point. These features and
the availability of the LTM4620EV in a compact 15mm ×
15mm × 4.41mm LGA package make it ideal for use in
many high-density point-of-load regulation applications.
The LTM4620 data sheet must be read in conjunction
with this demo manual prior to working on or modifying
DC1498A.
Design files for this circuit board are available at
http://www.linear.com/demo
L, LT, LTC, LTM, µModule, Linear Technology, the Linear logo and µModule are registered
trademarks of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
BoarD photo

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DEMO MANUAL DC1498A
Quick start proceDure
DC1498A is easy to set up to evaluate the performance
of the LTM4620EV. Please refer to Figure 1 for proper
measurement setup and follow the procedure below:
1. Place jumpers in the following positions for a typical
application:
JP1 JP2 JP3 JP4 JP5 JP6
MODE RUN1 RUN2 TRACK1
SEL.
TRACK2
SEL.
CLKOUT
PHASE
CCM ON ON Soft-Start Soft-Start 90°
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 to 12V.
3. Turn on the power supply at the input. The output volt-
age in channel 1 should be 1.5V ±1.5% (1.4775V to
1.525V) and the output voltage in channel 2 should be
1.2V ± 1.5% (1.182V to 1.218V).
4. Once the proper output voltage is established, adjust the
load within the operating range and observe the output
voltage regulation, output voltage ripple, efficiency and
other parameters. Output ripple should be measured
at J1 and J2 with BNC cables. 50Ω termination should
be set on the oscilloscope or BNC cables.
5. (Optional) For optional load transient test, apply an
adjustable pulse signal between IOSTEP CLK and GND
test point. Pulse amplitude (3V to 3.5V) sets the load
step current amplitude. The output transient current
can be monitored at the BNC connector J3 (15mV/A).
The pulse signal should have very small duty cycle
(<10%) to limit the thermal stress on the transient
load circuit. Switch the jumper resistors R34 or R35
(on the backside of boards) to apply load transient on
channel 1 or channel 2 correspondingly.
performance summary
(TA= 25°C)
PARAMETER CONDITIONS VALUE
Input Voltage Range 4.5V to 16V
Output Voltage VOUT1 VIN = 4.5V to 16V, IOUT1 = 0A to 12A, JP1: CCM 1.5V ±1.5% (1.4775V to 1.5225V)
Output Voltage VOUT2 VIN = 4.5V to 16V, IOUT2 = 0A to 12A, JP1: CCM 1.2V ±1.5% (1.182V to 1.218V)
Per-Channel Maximum Continuous Output Current Derating is Necessary for Certain VIN, VOUT and Thermal
Conditions. See data sheet for detail.
13A (Per Channel)
Default Operating Frequency 600kHz
Resistor Programmable Frequency Range 250kHz to 780kHz
External Clock Synchronous Frequency Range 400kHz to 780kHz
Efficiency of Channel 1 VIN = 5V, VOUT1 = 1.5V, IOUT1 = 13A, fSW = 600kHz 87.7% See Figure 2
Efficiency of Channel 2 VIN = 5V, VOUT2 = 1.2V, IOUT2 = 13A, fSW = 600kHz 85.1% See Figure 3
Load Transient of Channel 1 VIN = 12V, VOUT1 = 1.5V, ISETP = 0A to 6A See Figure 4
Load Transient of Channel 2 VIN = 12V, VOUT2 = 1.2V, ISETP = 0A to 6A See Figure 5
LTM4620 Demo Cards for Up to 100A Point-of-Load Regulation
MAXIMUM OUTPUT CURRENT (A) NUMBER OF OUTPUT VOLTAGES
NUMBER OF LTM4620 µMODULE
REGULATORS ON THE BOARD DEMO CARD NUMBER
13, 13 2 1 DC1498A
50 1 2 DC1780A-A
75 1 3 DC1780A-B
100 1 4 DC1780A-C

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DEMO MANUAL DC1498A
Figure 1. Test Setup of DC1498A
Quick start proceDure
6. (Optional) LTM4620 can be synchronized to an external
clock signal. Place the JP1 jumper on EXT_CLK and
apply a clock signal (0V to 5V, square wave) on the
CLKIN test point.
7. (Optional) The outputs of LTM4620 can track another
supply. The jumpers JP4 and JP5 allow choosing soft-
start or output tracking. If tracking external voltage is
selected, the corresponding test points, TRACK1 and
TRACK2, need to be connected to a valid voltage signal.
8. (Optional) LTM4620 can be configured for a 2-phase
single output at up to 26A on DC1498A. Install 0Ω
resistors on R14, R17, R28, R39 and remove R7, R19.
Output voltage is set by R25 based on equation VOUT =
0.6V (1 + 60.4k/R25).

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DEMO MANUAL DC1498A
Quick start proceDure
Figure 2. Measured Efficiency on Channel 1.
VOUT1 = 1.5V, fSW = 600kHz, Channel 2 Disabled
Figure 3. Measured Efficiency on Channel 2
VOUT2 = 1.2V, fSW = 600kHz, Channel 1 Disabled
LOAD CURRENT (A)
0
EFFICIENCY (%)
95
85
90
80
70
75
65
60 82
DC1498A F02
146 12104
VIN = 5V
VIN = 9V
VIN = 12V
VIN = 15V
LOAD CURRENT (A)
0
EFFICIENCY (%)
95
85
90
80
70
75
65
60 82
DC1498A F03
146 12104
VIN = 5V
VIN = 9V
VIN = 12V
VIN = 15V
Figure 4. Measured Channel 1
0A to 6A Load Transient, VIN = 12V, VOUT1 = 1.5V
Figure 5. Measured Channel 2
0A to 6A Load Transient, VIN = 12V, VOUT2 = 1.2V
100µs/DIV
100mV/DIV
DC1498A F04
1.5VOUT (20MHz BW)
0A TO 6A LOAD STEP
100µs/DIV
100mV/DIV
DC1498A F05
1.2VOUT (20MHz BW)
0A TO 6A LOAD STEP
5µs/DIV
50mV/DIV
50mV/DIV
DC1498A F06
1.5VOUT (20MHz BW)
1.2VOUT (20MHz BW)
Figure 6. Measured Output Voltage Ripple at 5V
Input, 1.5V and 1.2V Output, 13A Per Channel
with Standard Demo Circuit Default Setup

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DEMO MANUAL DC1498A
Quick start proceDure
Figure 7. Thermal Capture at 5VIN, 1.5VOUT at 12A and 1.2VOUT at 12A.
Ambient Temperature = 30°C, No Airflow and No Heat Sink
Figure 8. Thermal Capture at 5VIN, 1.5VOUT at 13A and 1.2VOUT at 13A.
Ambient Temperature = 30°C, No Airflow and No Heat Sink

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DEMO MANUAL DC1498A
Quick start proceDure
Figure 9. Thermal Capture at 12VIN, 1.5VOUT at 12A and 1.2VOUT at 12A.
Ambient Temperature = 30°C, No Airflow and No Heat Sink
Figure 10. Thermal Capture at 12VIN, 1.5VOUT at 13A and 1.2VOUT at 13A.
Ambient Temperature = 30°C, No Airflow and No Heat Sink

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DEMO MANUAL DC1498A
parts List
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER, PART NUMBER
Required Circuit Components
1 4 CIN2, CIN3, CIN4, CIN5 Capacitor, X5R, 22µF, 25V, 10%,1210 Murata, GRM32ER61E226KE15
2 2 COUT1, COUT7 Capacitor, 470µF, 4V, POSCAP, F8 Sanyo, 4TPE470MCL
3 2 COUT4, COUT5 Capacitor, X5R, 100µF, 6.3V, 20% 1210 AVX, 12106D107MAT2A
4 3 R3, R22, R26 Resistor, Chip, 10k, 1%, 0603 NIC, NRC06F10R0TRF
5 1 R19 Resistor, Chip, 60.4k, 1%, 0603 Vishay, CRCW060360K4FKED
6 1 R25 Resistor, Chip, 40.2k, 1%, 0603 Vishay, CRCW060340K2FKED
7 1 R30 Resistor, Chip, 158k, 1%, 0603 Vishay, CRCW0603158KFKED
8 1 U1 LTM4620EV, 15mm × 15mm × 4.41mm LGA Linear Technology, LTM4620EV
Additional Demo Board Circuit Components
9 1 CIN1 Capacitor, 150µF, 25V, Aluminum Electr. Sun Electronics, 25CE150AX
10 0 COUT2, COUT3, COUT6, COUT8 Optional 1210
11 0 C1 Optional, 0805
12 1 C2 Capacitor, X7R, 1µF, 25V, 10%, 0805 AVX, 08053C105KAT2A
13 2 C5, C7 Capacitor, X5R, 0.1µF, 25V, 10%, 0603 AVX, 06033D104KAT
14 0 C3, C4, C6, C8-C12 Optional, 0603
15 2 C13, C14 Capacitor, X5R, 0.01µF, 50V, 10%, 0603 AVX, 06035C103KAT
16 2 C15, C16 Capacitor, X7R, 1µF, 10V, 10%, 0603 AVX, 0603ZC105KAT
17 1 Q1 N-Channel 30V MOSFET Vishay, SUD50N03-09P
18 1 R1 Resistor, Chip, 10k, 1%, 0603 NIC, NRC06F10R0TRF
19 0 R2, R4, R6, R8, R11, R14, R16, R17, R20 R23, R28, R31, R33, R39, R40 Optional, 0603
20 4 R5, R24, R27, R36 Resistor, Chip, 10k, 1%, 0603 Vishay, CRCW060310K0FKED
21 4 R7, R21, R29, R32 Resistor, Chip, 0k, 1%, 0603 Vishay, CRCW06030000Z0ED
22 5 R9, R12, R15, R18 Resistor, Chip, 60.4k, 1%, 0603 Vishay, CRCW060360K4FKED
23 2 R10, R13 Resistor, Chip, 6.04k, 1%, 0603 Vishay, CRCW06036K04FKED
24 1 R34 Resistor, Chip, 0Ω, 0.5W, 2010 Vishay, CRCW20200000Z0EF
25 0 R35 Optional, 2010
26 1 R37 Resistor, Chip, 0.015Ω, 2W, 2512 Vishay, WSL2512R0150FEA
27 0 R38 Optional, 2512
Hardware – For Demo Board Only
28 16 E1, E3-E10, E12-E16 Testpoint, Turret, 0.094" PBF Mill-Max, 2501-2-00-80-00-00-07-0
29 3 J1, J2, J3 Conn, BNC, 5 Pins Connex 112404
30 6 J4–J9 Jack Banana Keystone, 575-4
31 1 JP1 Header 4 Pin 0.079 Double Row Samtec, TMM104-02-L-D
32 1 JP6 Header 4 Pin 0.079 Single Row Samtec, TMM104-02-L-S
33 3 JP2, JP3, JP4 Header 3 Pin 0.079 Single Row Samtec, TMM103-02-L-S
34 1 JP5 Header 3 Pin 0.079 Double Row Samtec, TMM-103-02-L-D
35 6 XJP1–XJP6 Shunt, 0.079" Center Samtec, 2SN-BK-G
36 4 (Stand-Off) Stand-Off, Nylon 0.50" Keystone, 8833 (Snap On)

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DEMO MANUAL DC1498A
schematic Diagrams
5 5
4 4
3 3
2 2
1 1
D D C C B B A A
VIN+
VIN-
VIN GND
4.5V-16V
VOUT1
GND VO1+ VO1-
1.5V @ 12A
1.2V @ 12A
GND
VO2- VO2+
VOUT2
ON
TRACK1
CLKOUT
PHASE
120
90
60
o
o o
ON
EXT.
SOFT-START
TRACK1 SEL.
  
m
VOUT1
VIN INTVCC
VO1+
VO1-
INTVCC
VO1-
VO1+
INTVCC
INTVCC
VOUT1
VO2+
VO2-
VIN
INTVCC
DIFFP
COMP1
VFB1
DIFFN
DIFFOUT
VOUT1S
VOUT1
TRACK1
RUN1
VO2+
VOUT2
VO2-
VOUT2S RUN2
TRACK2
VFB2 COMP2
INTVCC
TEMP
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
TECHNOLOGY 
   

        













 
 
 




TECHNOLOGY 
   

        













E4E4
J6J6
R16
OPT
R16
OPT
J7J7
JP3
OFF
RUN2
JP3
OFF
RUN2
13
2
E15
TEMP
E15
TEMP
E7E7
COUT3 OPT COUT3 OPT
C10 OPT C10 OPT
R19
60.4K
R19
60.4K
C5 0.1uF C5 0.1uF
J4J4
R3 10 R3 10
E1E1
CIN4 22uF
1210 25V
CIN4 22uF
1210 25V COUT2
OPT COUT2 OPT
COUT6 OPT COUT6 OPT
+
COUT1
470uF 4V
+
COUT1
470uF 4V
C4
OPT
C4
OPT
C3 OPT C3 OPT
R10 6.04K R10 6.04K
JP1
EXT_CLK
PS
CCM
MODE
BM
JP1
EXT_CLK
PS
CCM
MODE
BM
1 3
2 4 65
7 8
J5J5
R30 158K R30 158K
J8J8
U1
LTM4620EV
U1
LTM4620EV
VIN J9
VIN J10
VIN J11
VIN K2
VIN K3
VIN K4
VIN K9
VIN K10
VIN K11
VIN
M2
VIN
M3
VIN
M4
VIN
M5
VIN
M6
VIN
M7
VIN
M8
VIN
M9
VIN
M10
VIN
M11
VIN L2
VIN L3
VIN L4
VIN L5
VIN L6
VIN L7
VIN L8
VIN L9
VIN
L10
VIN
L11
VIN J2
VIN J3
VIN J4
RUN1
F5
TRACK1
E5
VOUT1S
C5
VOUT1
A1
VOUT1
A2
VOUT1
A3
VOUT1
A4
VOUT1
A5
VFB1
D5
SW1
G2
PGOOD1
G9
COMP1
E6
DIFFOUT
F8
DIFFN
E9
DIFFP
E8
FSET
C6
PHASMD
G4
GND
A6
GND
A7
GND
B6
GND
B7
GND
D1
GND
D2
GND
D3
GND
D4
GND
D9
GND
D10
GND
D11
GND
D12
GND
E1
GND
E2
GND
E3
GND
E4
GND
E10
GND
E11
GND
E12
GND
F1
GND
F2
GND
F3
GND
F10
GND
F11
GND
F12
GND
G1
GND
G10
GND
G12
GND
H1
GND
H2
GND H3 GND H4 GND H5 GND H6 GND H7 GND H9 GND H10 GND H11 GND H12 GND J1 GND J5 GND J8 GND J12 GND K1 GND K5 GND K6 GND K7 GND K8 GND K12 GND L1 GND L12 GND M1 GND M12
SGND C7 SGND D6 SGND F6 SGND F7 SGND G6 SGND G7
VOUT1
B1
VOUT1
B2
VOUT1
B3
VOUT1
B4
VOUT1
B5
VOUT1
C1
VOUT1
C2
VOUT1
C3
VOUT1
C4
COMP2 E7
PGOOD2 G8
SW2 G11
VFB2 D7
TRACK2 D8
RUN2 F9
VOUT2S C8
TEMP J6
MODE-PLLIN F4
CLKOUT G5
INTVCC H8
EXTVCC J7
VOUT2 A8
VOUT2 A9
VOUT2 A10
VOUT2 A11
VOUT2 A12
VOUT2 B8
VOUT2 B9
VOUT2 B10
VOUT2 B11
VOUT2 B12
VOUT2 C9
VOUT2 C10
VOUT2 C11
VOUT2 C12
GND
G3
JP5
VOUT1
TRACK2 SEL. JP5
VOUT1
TRACK2 SEL.
1 3
2 4
5 6
C7
0.1uF
C7
0.1uF
E12 PGOOD2 E12 PGOOD2
E13
EXTVCC
E13
EXTVCC
CIN3 22uF
25V
1210 CIN3 22uF
25V
1210
R15
60.4K
R15
60.4K
R32
0
R32
0
R1 10 R1 10
C6
OPT
C6
OPT
E6E6
CIN2 22uF
25V
1210
CIN2 22uF
25V
1210
R21 0 R21 0
COUT4 100uF
6.3V
COUT4 100uF
6.3V
E14
CLKOUT
E14
CLKOUT
R7 0 R7 0
COUT8 OPT COUT8 OPT
C1
OPT
C1
OPT
R22 10 R22 10
J9J9
C2 1uF C2 1uF
R20 OPT R20 OPT
E8E8
R2
OPT
R2
OPT
R6 OPT R6 OPT
R24
10K
R24
10K
C12
OPT
C12
OPT
R27 10K R27 10K
+
COUT7
470uF 4V
+
COUT7
470uF 4V
CIN5 22uF
25V
1210
CIN5 22uF
25V
1210
JP2
OFF
RUN1
JP2
OFF
RUN1
1 3
2
R5 10K R5 10K
R8
OPT
R8
OPT
C11
OPT
C11
OPT
JP6JP6
1 3 2
4
R18 60.4K R18 60.4K
E10 TRACK2 E10 TRACK2
R9 60.4K R9 60.4K
+
CIN1
150uF 25V
+
CIN1
150uF 25V
E9E9
TP1
SW1
TP1
SW1
R12 60.4K R12 60.4K
C8
OPT
C8
OPT
E3
PGOOD1
E3
PGOOD1
C9
OPT
C9
OPT
R26
10
R26
10
JP4
SOFT-START
TRACK
JP4
SOFT-START
TRACK
1
3
2
E5E5
COUT5
100uF
6.3V
COUT5
100uF
6.3V
R13
6.04K
R13
6.04K
E16
CLKIN
E16
CLKIN
R29
0
R29
0
TP2 SW2 TP2 SW2
R25
40.2K
R25
40.2K
R4 OPT R4 OPT

9
dc1498afa
DEMO MANUAL DC1498A
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 representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
schematic Diagrams
5 5
4 4
3 3
2 2
1 1
D D C C B B A A
OPTIONAL JUMPER FOR 1 OUTPUT CONFIGURATION
DIFF SENSING SELECTION
VOUT1
m
Load Transient Circuit
VOUT2
TEMP INTVCC
RUN1 RUN2
TRACK1 TRACK2
VFB1 VFB2
COMP1 COMP2
VO2- DIFFN VO2+ DIFFP
VOUT1S VOUT1 VOUT2S DIFFOUT
VOUT1 VOUT2
 
 
 




TECHNOLOGY
    

        













 
 
 




TECHNOLOGY
    

        













 
 
 




TECHNOLOGY
    

        













E17
IOSTEP CLK
E17
IOSTEP CLK
R36 10K R36 10K
R39 OPT R39 OPT
R23
OPT
R23
OPT
J3
IOSTEP
J3
IOSTEP
Q1 SUD50N03-09P Q1 SUD50N03-09P
2
1
3
4
R35
OPT
2010
R35
OPT
2010
C13
0.01uF
C13
0.01uF
R14 OPT R14 OPT
J1J1
R11
OPT
R11
OPT
C14
0.01uF
C14
0.01uF
E18
GND
E18
GND
R34
0 OHm
0.5W 2010 R34
0 OHm
0.5W 2010
R28 OPT R28 OPT
R38
OPT 2512
R38
OPT 2512
R33
OPT
R33
OPT
R40
OPT
R40
OPT
C16 1uF C16 1uF
R17 OPT R17 OPT
R37
0.015 2W 2512
R37
0.015 2W 2512
J2J2
R31
OPT
R31
OPT
C15 1uF C15 1uF

10
dc1498afa
DEMO MANUAL DC1498A
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ●FAX: [phone] ●www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2012
LT 0413 REV A • PRINTED IN USA
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 applica-
tion engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation

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