Linear Technology DC2603A-A Quick setup guide

1
dc2603aaf
DEMO MANUAL DC2603A-A
DESCRIPTION
LTM4650AEY
Dual 25A or Single 50A
DC/DC μModule Regulator
Demonstration circuit 2603A-A features the
LT M ®4650AEY-1, the high efficiency, high density, dual
25A, single 50A switch mode step-down power mod-
ule regulator. The input voltage is from 4.5V to 16V.
The output voltage is programmable from 0.6V to 5.5V.
DC2603A-A can deliver 25A maximum current from each
channel. The board designs with minimum components to
demonstrate this high efficiency, high density µModule®.
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 for noise sensitive applications or Burst Mode
®
operation in less noise sensitive applications. Two out-
puts can be connected in parallel for a single 50A out-
L, LT, LTC, LTM, BUrst Mode, µModule, Linear Technology and the Linear logo are registered
trademarks of Analog Devices, Inc. All other trademarks are the property of their respective
owners.
BOARD PHOTO
put 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 sens-
ing is available for improved output voltage regulation at
the load point. These features and the availability of the
LTM4650AEY in a compact 16mm ×16mm ×5.01mm
BGA package make it ideal for use in many high-density
point-of-load applications. The LTM4650Adata sheet
must be read in conjunction with this demo manual for
working on or modifying the demo circuit DC2603A-A.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2603A-A
Figure 1. LTM4650A/DC2603A-A Demo Board

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dc2603aaf
DEMO MANUAL DC2603A-A
QUICK START PROCEDURE
Demonstration circuit DC2603A-A is easy to set up to
evaluate the performance of the LTM4650AEY. Please
refer to Figure 2 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
MODE RUN1 RUN2 TRACK1 SEL TRACK2 SEL
CCM ON ON SOFT-START SOFT-START
2. With power off, connect the input power supply, load
and meters as shown in Figure 2. Preset the load to 0A
and VIN supply to 12V.
3. Turnonthepowersupplyattheinput.Theoutputvoltage
in channel 1 should be 1.5V± 1.0% (0.985V~1.015V)
andtheoutputvoltageinchannel2shouldbe3.3V±1.0%
(3.267V~3.333V)
4. Oncethe proper output voltage is established, adjustthe
load within the operating range and observe the output
voltage regulation, output voltage ripple, efficiency and
other parameters. Output ripple can 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~3.5V) sets the
loadstepcurrentamplitude.Theoutputtransientcurrent
can be monitored at the BNC connector J3 (10mV/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.
6. (Optional) LTM4650A can be synchronized to an
external clock signal. Place the JP1 jumper on EXT_CLK
and apply a clock signal (0V~5V, square wave) on the
CLKIN test point.
7. (Optional)TheoutputsofLTM4650A-1cantrackanother
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)LTM4650A-1canbeconfigured for a2-phase
singleoutputatupto50AonDC2603A-A.Install0Ωresis-
tors on R14, R17, R28, R39, R43, R44, R45 and remove
R7,R19. Output voltage is set byR25based onequation:
VOUT =0.6V • 1+60.4k
R25
⎛
⎝
⎜⎞
⎠
⎟
PERFORMANCE SUMMARY
Specifications are at TA= 25°C
PARAMETER CONDITIONS VALUE
Input Voltage Range 4.5V ~ 16V
Output Voltage VOUT1 VIN = 4.5~16V, IOUT1 = 0~25A, JP1: CCM 1.5V ± 1% (1.485V ~ 1.515V)
Output Voltage VOUT2 VIN = 4.5~16V, IOUT1 = 0~25A, JP1: CCM 3.3V ± 1% (3.267V ~ 3.333V)
Per- Channel Maximum Continuous Output
Current
De-rating is Necessary for Certain VIN, VOUT and Thermal
Conditions, see Data Sheet for Detail
25A
Default Operating Frequency 600kHz
Resistor Programmable Frequency Range 250kHz to 780kHz
External Clock Sync. Frequency Range 400kHz to 780kHz
Efficiency of Channel 1 VIN = 12V, VOUT = 1.5V, IOUT = 25A, fSW = 600 kHz 90.4%, See Figure 3
Efficiency of Channel 2 VIN = 12V, VOUT = 3.3V, IOUT = 25A, fSW = 600 kHz 94.2%, See Figure 4
Load Transient of Channel 1 VIN = 12V, VOUT = 1.5V, ISTEP = 12.5~18.75A < ±3% (90mVP-P), See Figure 5
Load Transient of Channel 2 VIN = 12V, VOUT = 3.3V, ISTEP = 12.5~18.75A < ±3% (198mVP-P), See Figure 6

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dc2603aaf
DEMO MANUAL DC2603A-A
QUICK START PROCEDURE
Figure 2. Test Setup of DC2603A-A
LOAD1 (0~25A)
dc2603aaf
1mΩ
VOUT1
VIN
4.5V-16V
VOUT2
–+–
+
LOAD2 (0~25A)
1mΩ
+ –+
–
+ –
+ –+
–

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dc2603aaf
DEMO MANUAL DC2603A-A
84.6
91.5
94.4 94.7 94.7 94.2
94.9
96.7 97.1 96.5 95.9
95.2
80
85
90
95
100
0 5 10 15 20 25
EFFICIENCY (%)
OUTPUT LOAD CURRENT (A)
VIN=12V VIN=5V
QUICK START PROCEDURE
Figure 3. Measured Efficiency on Channel 1 (VOUT1 = 1.5V, fSW = 600kHz, Channel2 Disabled)
Efficiency vs Load Current at VO = 3.3V, fSW = 600kHz
Efficiency vs Load Current at VO = 1.5V, fSW = 600kHz
Figure 4. Measured Efficiency on Channel 2 (VOUT2 = 3.3V, fSW = 600kHz, Channel1 Disabled)
83.4
88.9
91.8 91.6 90.9 90.4
90.3
93.0
94.0
93.1
92.2
90.7
80
85
90
95
100
0 5 10 15 20 25
EFFICIENCY (%)
OUTPUT LOAD CURRENT (A)
VIN=12V VIN=5V

5
dc2603aaf
DEMO MANUAL DC2603A-A
QUICK START PROCEDURE
Figure 5. Measured Channel 1 12.5A-18.75A Load Transient (VIN = 12V, VOUT1 = 1.5V)
Figure 6. Measured Channel 2 12.5A-18.75A Load Transient (VIN = 12V, VOUT2 = 3.3V)
3.3V Output (20MHz BW) [50mV/Div]
12.5A-18.75A Load Step
1.5V Output (20MHz BW) [20mV/Div]
12.5A-18.75A Load Step

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dc2603aaf
DEMO MANUAL DC2603A-A
QUICK START PROCEDURE
Figure 7. Measured Output Voltage Ripple at 12V Voltage Input, 1.5V/25A, fSW = 600kHz, Measured Across COUT6 Using 1×Probe
Figure 8. Measured Output Voltage Ripple at 12V Voltage Input, 3.3V/25A, fSW = 600kHz, Measured Across COUT2 Using 1×Probe

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dc2603aaf
DEMO MANUAL DC2603A-A
QUICK START PROCEDURE
Figure 9. Thermal Performance at VIN = 12V, VOUT1 = 1.5V/25A, VOUT2 = 3.3V/25A, fSW = 600kHz, TA= 23 °C, No Forced Air Airflow

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dc2603aaf
DEMO MANUAL DC2603A-A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 1 CIN1 CAP., 330µF, ALUM, OS-CON, 25V, 20%, SMD
10mm ×12.6mm, F12, SVPF Series
PANASONIC, 25SVPF330M
2 4 CIN2,CIN3,CIN4,CIN5 CAP., 22µF, X5R, 25V, 10%,1210 MURATA, GRM32ER61E226KE15L
3 6 COUT2, COUT6, COUT13,
COUT14, COUT15, COUT16
CAP., 100µF, X5R, 6.3V, 20%, 1210 AVX, 12106D107MAT2A
4 4 COUT3, COUT4, COUT5, COUT8 CAP., 100µF, X5R, 6.3V, 20%, 1210 AVX, 12106D107MAT2A
5 4 COUT9, COUT10, COUT12,
COUT18
CAP., 330µF, TANT, POSCAP, 6.3V, 20%, 7343,
D3L, TPE Series
PANASONIC, 6TPE330ML
6 1 C1 CAP., 4.7µF, X5R, 16V, 20%, 0805 KEMET, C0805C475M4PACTU
7 1 C2 CAP., 1µF, X7R, 25V,10%, 0805 AVX, 08053C105KAT2A
8 2 C5,C7 CAP., 0.1µF, X5R, 25V, 10%, 0603 AVX, 06033D104KAT2A
9 4 C13, C14, C15, C16 CAP., 1µF, X7R, 10V,10%, 0603 AVX, 0603ZC105KAT2A
10 4 R1, R3, R22, R26 RES., 10Ω, 1/10W, 1%, 0603 VISHAY, CRCW060310R0FKEA
11 1 R5 RES., 100k, 1/10W, 1%, 0603 VISHAY, CRCW0603100KFKEA
12 4 R9, R12, R15, R18 RES.., 60.4k, 1/10W, 1%, 0603 VISHAY, CRCW060360K4FKEA
13 2 R10, R13 RES.., 6.04k, 1/10W, 1%, 0603 VISHAY, CRCW06036K04FKEA
14 1 R19 RES., 13.3k, 1/10W, 1%, 0603 VISHAY, CRCW060313K3FKEA
15 3 R24, R27, R36 RES., 10k, 1/10W, 1%, 0603 VISHAY, CRCW060310K0FKEA
16 1 R25 RES., 40.2k, 1/10W, 1%, 0603 VISHAY, CRCW060340K2FKDA
17 1 R30 RES., 147k, 1/10W, 1%, 0603 VISHAY, CRCW0603147KFKEA
18 1 R37 RES., HIGH POWER, 0.01Ω, 2W, 1%, 2512 VISHAY, WSL2512R0100FEA18
19 1 U1 I.C., 16 ×16 ×5.01 BGA Linear Tech, LTM4650AEY#PBF
Additional Demo Board Circuit Components
1 0 COUT1, COUT7, COUT11,
COUT17
CAP., OPT, 7343 OPT
2 0 C3, C4, C8, C11 CAP., OPTION, 0603 OPT
3 0 C6, C9, C10, C12, C17, C18 CAP., OPT, 0603 OPT
4 0 R2, R4, R6, R8, R11, R14, R16,
R17, R20, R23, R28, R31, R33,
R39, R40, R41, R42, R46, R47,
R48
RES., OPTION, 0603 OPT
5 4 R7, R21, R29, R32 RES., 0Ω, 1/10W, 0603 VISHAY, CRCW06030000Z0EA
6 1 R34 RES., 0Ω, 3/4W, 2010 VISHAY, CRCW20100000Z0EF
7 0 R35 RES., OPTION, 2010 OPT

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dc2603aaf
DEMO MANUAL DC2603A-A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
8 0 R38, R43, R44, R45 RES., OPTION, 2512 OPT
Hardware: For Demo Board Only
1 16 E1, E3, E4, E5, E6, E7, E8, E9,
E10, E12, E13, E14, E15, E16,
E17, E18
TEST POINT, TURRET, .094" MTG. HOLE MILL-MAX, 2501-2-00-80-00-00-07-0
2 1 JP1 CONN., HDR, MALE, 2 ×4, 2mm, THT, STR WURTH ELEKTRONIK, 62000821121
3 3 JP2, JP3, JP4 CONN., HDR, MALE, 1 ×3, 2mm, THT, STR WURTH ELEKTRONIK, 62000311121
4 1 JP5 CONN., HDR, MALE, 2 ×3, 2mm, THT, STR WURTH ELEKTRONIK, 62000621121
5 5 XJP1, XJP2, XJP3, XJP4, XJP5 CONN., SHUNT, FEMALE, 2 POS, 2mm WURTH ELEKTRONIK, 60800213421
6 3 J1, J2, J3 CONN., RF, BNC, RCPT, THT, STR, 5-PIN AMPHENOL CONNEX 112404
7 2 J4, J5 CONN., BANANA JACK, FEMALE, THT,
NON-INSULATED, SWAGE, 0.218"
KEYSTONE, 575-4
8 4 J6, J7, J8, J9 STUD, FASTENER, #10-32 PennEngineering, KFH-032-10ET
9 8 J6, J7, J8, J9 (×2) NUT, HEX, STEEL, ZINC PLATE,10-32 KEYSTONE, 4705
10 4 J6, J7, J8, J9 RING, LUG, CRIMP, #10, NON-INSULATED,
SOLDERLESS TERMINALS
KEYSTONE, 8205
11 4 J6, J7, J8, J9 WASHER, FLAT, STEEL, ZINC PLATE, OD: 0.436
[11.1]
KEYSTONE, 4703
12 4 (STAND-OFF) STANDOFF, NYLON, SNAP-ON, 0.500" KEYSTONE, 8833

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dc2603aaf
DEMO MANUAL DC2603A-A
SCHEMATIC DIAGRAM
5
5
4
4
3
3
2
2
1
1
D D C C B B A A
VIN+
VIN-
VIN GND
4.5V-20V
VO1+ VO1-
VO2- VO2+
ON
TRACK1
ON
EXT.
SOFT-START
TRACK1 SEL.
NOTE: UNLESS OTHERWISE SPECIFIED 1. ALL RESISTORS AND CAPACITORS ARE 0603.
m
SW2
SW1
*
U1ASSY
LTM4650AEY‐A
‐B
C10 OPT
220pF
R46,R47
OPT 10KLTM4650AEY‐1
C12 OPT 47pF
C17 OPT 3.3nF
C18 OPT 4.7nF
C6,C9
OPT
33pF
COUT9,10,12,18
330uF(7343)
OPT
COUT2,6,13,14,15,16
100uF(1210) 330uF(1210)
VOUT1
VIN INTVCC
VO1+
VO1-
INTVCC
VO1-
VO1+
INTVCC
VOUT1
VO2+
VO2-
VIN
INTVCC
INTVCC
DIFFP
COMP1
VFB1
DIFFN
DIFFOUT
VOUT1S
VOUT1
TRACK1
RUN1
VO2+
VOUT2
VO2-
VOUT2S
RUN2
TRACK2
VFB2
COMP2
INTVCCTEMP
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
PROTOTYPE
1 03-28-17
__
ST
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
PROTOTYPE
1 03-28-17
__
ST
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
PROTOTYPE
1 03-28-17
__
ST
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
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
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
1
Tuesday, March 28, 2017
12
DC/DC MODULE REGULATOR
LT
ST
N/A
LTM4650AEY / LTM4650AEY-1
DEMO CIRCUIT 2603A(A,B)
HIGH EFFICIENCY, DUAL 25A OR SINGLE 50A,
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
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
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
1
Tuesday, March 28, 2017
12
DC/DC MODULE REGULATOR
LT
ST
N/A
LTM4650AEY / LTM4650AEY-1
DEMO CIRCUIT 2603A(A,B)
HIGH EFFICIENCY, DUAL 25A OR SINGLE 50A,
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
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
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
1
Tuesday, March 28, 2017
12
DC/DC MODULE REGULATOR
LT
ST
N/A
LTM4650AEY / LTM4650AEY-1
DEMO CIRCUIT 2603A(A,B)
HIGH EFFICIENCY, DUAL 25A OR SINGLE 50A,
E15
TEMP
JP3
OFF
RUN2
13
2
R16
OPT
E4
COUT14 * 6.3V
1210
C10*
E7
COUT13 * 6.3V
COUT6* 6.3V 1210
COUT2 * 6.3V
CIN4 22uF
1210 25V
E1
J4
R3 10
C5
0.1uF
R19
13.3K
U1 *
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
R30 147K
J6
1.5V / 25A
VOUT1
J5
JP1
EXT_CLK
PS
CCM
MODE
BM
1 3
2 4 65
7 8
R10 6.04K
C3
OPT C4
OPT
+
COUT1 OPT 6.3V
E12 PGOOD2
R46 *
C7
0.1uF
JP5
VOUT1
TRACK2 SEL.
1 3
2 4
5 6
R32
0
R15 60.4K
CIN3 22uF
25V
1210
E13
EXTVCC
+
COUT10 *
6.3V
7343
+
COUT18
*
6.3V 7343
+
COUT17
OPT 7343
C6
*
R1 10
COUT16 *
6.3V
COUT15 *
6.3V 1210
R22 10
C1
4.7uF
R7 0
E14
CLKOUT
COUT4 100uF
6.3V
1210
R21
0
CIN2 22uF
25V
1210
E6
R42 OPT
E8
R20 OPT
R47*
C2
1uF
CIN5 22uF
25V
1210
+
COUT7
OPT 7343
R27
10K
J9
GND
C12*
R24 10K
R41 OPT
R6 OPT
R2
OPT
COUT8
100uF
6.3V
C11
OPT
R8
OPT
R5
100K
JP2
OFF
RUN1
1 3
2
+
COUT12 *
6.3V
7343
E10
TRACK2
R18 60.4K
C17 *
E9
+
CIN1
330uF 25V
R9
60.4K
JP4
SOFT-START
TRACK
1
3
2
+
COUT11 OPT 6.3V 7343
R26
10
C9 *
E3
PGOOD1
C8
OPT
R12
60.4K
J7
GND
C18*
R13 6.04K
COUT5
100uF
6.3V
1210
E5
R29
0
E16
CLKIN
R4
OPT
+
COUT9
*
6.3V 7343
COUT3 100uF
6.3V
1210
R25
40.2K
J8
3.3V / 25A
VOUT2

11
dc2603aaf
DEMO MANUAL DC2603A-A
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 DIAGRAM
5
5
4
4
3
3
2
2
1
1
D D C C B B A A
OPTIONAL JUMPER FOR SINGLE OUTPUT CONFIGURATION
DIFF SENSING SELECTION
VOUT1
Load Transient Circuit
VOUT2
m
VIN
TEMP INTVCC
RUN1 RUN2
TRACK1 TRACK2
VFB1 VFB2
COMP1 COMP2
VO2- DIFFN VO2+ DIFFP
VOUT1S VOUT1 VOUT2S DIFFOUT
VOUT1 VOUT2
VOUT1 VOUT2
INTVCC
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
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
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
1
Tuesday, March 28, 2017
22
DC/DC MODULE REGULATOR
LT
ST
N/A
LTM4650AEY / LTM4650AEY-1
DEMO CIRCUIT 2603A(A,B)
HIGH EFFICIENCY, DUAL 25A OR SINGLE 50A,
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
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
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
1
Tuesday, March 28, 2017
22
DC/DC MODULE REGULATOR
LT
ST
N/A
LTM4650AEY / LTM4650AEY-1
DEMO CIRCUIT 2603A(A,B)
HIGH EFFICIENCY, DUAL 25A OR SINGLE 50A,
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
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
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
1
Tuesday, March 28, 2017
22
DC/DC MODULE REGULATOR
LT
ST
N/A
LTM4650AEY / LTM4650AEY-1
DEMO CIRCUIT 2603A(A,B)
HIGH EFFICIENCY, DUAL 25A OR SINGLE 50A,
R36
10K
E17
IOSTEP CLK
J3
IOSTEP
R23
OPT
R39
OPT C13
1uF
R35 OPT
2010
Q1 SUD50N04-8M8P-4GE3
2
1
34
R14
OPT
R48
OPT
J1 C14
1uF
R11
OPT
E18
GND
R34
0 OHm
0.5W 2010
R43 OPT 2512
R28
OPT
R45
OPT 2512
R38 OPT
2512
R33
OPT
R17
OPT C16
1uF
R44
OPT 2512
R40
OPT
C15 1uF
R31
OPT
J2
R37
0.010 2W 2512

12
dc2603aaf
DEMO MANUAL DC2603A-A
 LINEAR TECHNOLOGY CORPORATION 2017
LT 0617 • 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 application
engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation