Linear Technology DC1626A Quick setup guide

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dc1626afa
DEMO MANUAL DC1626A
DESCRIPTION
LTC3838EFE
Wide Input Range, High Efficiency
Step-Down DC/DC Converter
Demonstration circuit 1626A is a dual output 1.5V/15A
and 1.2V/15A synchronous buck converter operating with
a switching frequency of 300kHz over an input voltage
range of 4.5V to 26V. The demo board comes in two ver-
sions. The -A version uses inductor DCR current sensing
with an iron powder inductor for high efficiency. The -B
version uses a 2.5mΩ sense resistor for accurate current
sensing with a low DCR ferrite inductor. The fixed on-time
valley current mode architecture of the LTC3838 allows for
a fast load step response (see Figures 6 to 9). The load
step response can be tested with the on-board load step
circuit and a bench pulse generator.
The demo board uses a high density, two sided drop-in
layout. The entire converter, excluding the bulk output and
input capacitors, fits within a compact 1.5" ×1.0" area
on the board. The package style for the LTC3838EFE is a
38-lead TSSOP with an exposed ground pad.
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.
PERFORMANCE SUMMARY
The main features of the board are listed below:
• MODE jumper to program either DCM or FCM at light
or no load
• EXTVCC pin
• PLLIN pin to synchronize the converter to an external
clock
• Remote sensing for VOUT1
• Optional resistors to tie the two phases together
• Each rail has its own RUN pin, PGOOD pin and
TRACK/SS pin
Design files for this circuit board are available at
http://www.linear.com/demo
(TA= 25°C)
PARAMETER CONDITION VALUE
Minimum Input Voltage 4.5V
Maximum Input Voltage 26V
Output Voltage VOUT1 IOUT1 = 0A to 15A, VIN = 4.5V to 26V 1.2V ±2%
Output Voltage VOUT2 IOUT2 = 0A to 15A, VIN = 4.5V to 26V 1.5V ±2%
VOUT1 Maximum Output Current, IOUT1 VIN = 4.5V to 26V, VOUT1 = 1.2V 15A
VOUT2 Maximum Output Current, IOUT2 VIN = 4.5V to 26V, VOUT2 = 1.5V 15A
Nominal Switching Frequency 300kHz
-A Efficiency
See Figures 2 and 3
VOUT1 = 1.2V, IOUT1 = 15A, VIN = 12V 89.1% Typical
VOUT2 = 1.5V, IOUT2 = 15A, VIN = 12V 90.2% Typical
-B Efficiency
See Figures 4 and 5
VOUT1 = 1.2V, IOUT1 = 15A, VIN = 12V 85.9%
VOUT2 = 1.5V, IOUT2 = 15A, VIN = 12V 88.2%

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DEMO MANUAL DC1626A
QUICK START PROCEDURE
Demonstration circuit 1626A is easy to set up to evalu-
ate the performance of the LTC3838EFE. Please refer to
Figure1 for proper measurement equipment setup and
follow the procedure below.
1. With power off, connect the input supply, load and
meters as shown in Figure 1. Preset the load to 0A
and VIN supply to be 0V. Place jumpers in the following
positions:
JP4 RUN1 ON
JP1 RUN2 ON
JP3 MODE FCM
2. Adjust the input voltage to be between 4.5V to 26V.
VOUT1 should 1.2V ±2%.
V
OUT2 should 1.5V ±2%.
3. Next, apply 15A load and recheck VOUT.
4. Once the DC regulation is confirmed, observe the output
voltage ripple, load step response, efficiency and other
parameters.
Note 1. Use the BNC connectors labeled VOUT1 or VOUT2
to measure the output voltage ripple.
Note 2. Do not apply the load from the VO1_SNS+ turret
to the VO1_SNS– turret or from the VO2+ turret to the
VO2– turret. These turrets are only intended to monitor
the voltage across COUT1 and COUT5 respectively. Heavy
load currents applied across these turrets may damage
the converter.
Load Step Transient Testing
Demonstration circuit 1626A provides a simple load step
circuit consisting of a MOSFET and sense resistor for each
rail. To apply a load step, follow the steps below.
1. Preset the amplitude of a pulse generator to 0.0V and
the duty cycle to 5% or less.
2. Connect the scope to the VOUT BNC connectors for
the rail under test with a coax cable. To monitor the
load step current, connect the scope probe across the
IOSTEP+/IOSTEP– turrets for that rail.
3. Connect the output of the pulse generator to the PULSE
GEN turret for the rail under test and connect the return
to one of the GND turrets.
4. With the converter running, slowly increase the ampli-
tude of the pulse generator output to provide the desired
load step pulse height. The scaling for the LOAD STEP
signal is 10mV/A.

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DEMO MANUAL DC1626A
QUICK START PROCEDURE
Figure 1. Proper Measurement Equipment Setup
Single Output/Dual Phase Operation
A single output/dual phase converter may be preferred for
high output current applications. The benefits of single
output/dual phase operation islower ripple current through
the input and output capacitors, faster load step response
andsimplifiedthermaldesign.Toimplementsingleoutput/
dual phase operation, make the following modifications:
• Tie VOUT1 to VOUT2 by tying together the exposed
copper pads on the VOUT shapes with pieces of heavy
copper foil.
• Tie VFB2 to INTVCC by stuffing 0Ω at R1. This will
disable the error amp for phase 2 and internally tie the
two ITH signals together.
• Remove the ITH compensation network, VFB divider
and TRACK/SS cap for phase 2.
• Tie VRNG1 to VRNG2 by stuffing 0Ω at R4.
• Tie RUN1 to RUN2 by stuffing 0Ω at R7.
• If the optional transient detect circuit is used, externally
tie the DTR1 pin to the DTR2 pin.
• Re-compensate if necessary.
Vin
su
pp
l
y
Iout2
A
+
Vout2
load
-
A
Iin
V
-
+
+
-
-
+V
Vout1
Vout2
+
-
Iout1
A
Vout1
load
+
-
V
Vin
*Monitor the voltage across COUT3 and
COUT7 for accurate efficiency measurements.
*
*

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DEMO MANUAL DC1626A
QUICK START PROCEDURE
LOAD CURRENT (A)
BOTH RAILS:
QTOP = RJK0305DPB
QBOTTOM = RJK0330DPB
L = VISHAY IHLP4040DZ-01 0.56μH
DCR = 1.7mΩ TYP, 1.8mΩ MAX
0
EFFICIENCY (%)
95
90
80
85
75 10515
dc1626a F02
20
1.5V
1.2V
LOAD CURRENT (A)
BOTH RAILS:
QTOP = RJK0305DPB
QBOTTOM = RJK0330DPB
L = WURTH 7443330068 0.68μH
DCR = 1.35mΩ ±10%
RSENSE = 2.5mΩ
0
EFFICIENCY (%)
95
90
80
85
75 10515
dc1626a F04
20
1.5V
1.2V
LOAD CURRENT (A)
BOTH RAILS:
QTOP = RJK0305DPB
QBOTTOM = RJK0330DPB
L = VISHAY IHLP4040DZ-01 0.56μH
DCR = 1.7mΩ TYP, 1.8mΩ MAX
0.01 10.1 10
dc1626a F03
100
EFFICIENCY (%)
100
10
90
70
50
30
80
60
40
20
0
1.2V
1.5V
FCM
DCM
LOAD CURRENT (A)
BOTH RAILS:
QTOP = RJK0305DPB
QBOTTOM = RJK0330DPB
L = WURTH 7443330068 0.68μH
DCR = 1.35mΩ ±10%
RSENSE = 2.5mΩ
0.01 10.1 10
dc1626a F05
100
EFFICIENCY (%)
100
10
90
70
50
30
80
60
40
20
0
1.2V
1.5V
FCM
DCM
Figure 2. Efficiency Curves for the DC1626A-A
(DCR Sense) in FCM
Figure 4. Efficiency Curves for the DC1626A-B
(RSENSE) in FCM
Figure 3. Efficiency Curves for the DC1626A-A
(DCR Sense) in FCM and DCM.
Figure 5. Efficiency Curves for the DC1626A-B
(RSENSE) in FCM and DCM

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DEMO MANUAL DC1626A
QUICK START PROCEDURE
dc1626a F06
LOAD STEP
5A/DIV
1.2VO(AC)
50mV/DIV
15A
5A
109mV
dc1626a F08
LOAD STEP
5A/DIV
1.2VO(AC)
50mV/DIV
15A
5A
114mV
dc1626a F07
LOAD STEP
5A/DIV
1.5VO(AC)
50mV/DIV
15A
5A
108mV
dc1626a F09
LOAD STEP
5A/DIV
1.5VO(AC)
50mV/DIV
15A
5A
108mV
Figure 6. Load Step Response of the 1.2V Rail on the DC1626A-A
(DCR Sense) at VIN = 12V. COUT = 2×Sanyo 2R5TPE330M9 ||
2×100μF X5R 6.3V 1206, L = 0.56μH, fSW = 300kHz
Figure 8. Load Step Response of the 1.2V Rail on the DC1626A-B
(RSENSE) At VIN = 12V. COUT = 2×Sanyo 2R5TPE330M9 || 2×100μF
X5R 6.3V 1206, L = 0.68μH, fSW = 300kHz
Figure 7. Load Step Response of the 1.5V Rail on the DC1626A-A
(DCR Sense) at VIN = 12V. COUT = 2×Sanyo 2R5TPE330M9 ||
2×100μF X5R 6.3V 1206, L = 0.56μH, fSW = 300kHz
Figure 9. Load Step Response of the 1.5V Rail on the DC1626A-B
(RSENSE) at VIN = 12V. COUT = 2×Sanyo 2R5TPE330M9 || 2×100μF
X5R 6.3V 1206, L = 0.68μH, fSW = 300kHz

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DEMO MANUAL DC1626A
1626A-A (DCR Sense)
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 1 C12 CAP, X7R 330pF 50V 0603 AVX 06035C331KAT2A
2 5 C3, C16, C4, C10, C13 CAP, X5R 0.1μF 50V 0603 AVX 06035D104KAT2A 
3 2 C5, C14 CAP, X5R 0.01μF 25V 0603 AAC 0603D103KAT2A
4 2 C6, C11 CAP, NPO 47pF 16V 0603 AVX 0603YA470KAT4A
5 1 C7 CAP, NPO 220pF 25V 0603 AVX 06033A221KAT2A
6 1 C8 CAP, X5R 4.7μF 16V 0805 AVX 0805YD475KAT2A
7 2 C9, C18 CAP, X5R 1μF 16V 0603 AVX 0603YD105KAT2A
8 2 CIN1, CIN2 CAP, 100μF 35V SIZE-F SUNCON 35HVH100M
9 3 CIN3, CIN4, CIN5 CAP, X5R 10μF 35V 1210 TAIYO YUDEN GMK325BJ106MN-T
10 4 COUT1, COUT2, COUT5, COUT6 CAP, 330μF 2.5V SIZE 7343 SANYO 2R5TPE330M9
11 4 COUT3, COUT4, COUT7, COUT8 CAP, X5R 100μF 6.3V 1206 MURATA GRM31CR60J107ME39L
12 2 D1, D2 DIODE, SCHOTTKY SOD-323 CENTRAL SEMI. CMDSH-4ETR
13 2 L1, L2 IND, 0.56μH VISHAY IHLP4040DZERR56M01
14 2 Q1, Q3 MOSFET, N-CHANNEL LFPAK RENESAS RJK0305DPB-00-J0
15 2 Q2, Q4 MOSFET, N-CHANNEL LFPAK RENESAS RJK0330DPB-00-J0
16 2 R12, R38 RES, 100k 1% 0603 VISHAY CRCW0603100KFKEA
17 1 R13 RES, 15k 1% 0603 VISHAY CRCW060315K0FKEA
18 4 R17, R23, R40, R46 RES, 10k 1% 0603 VISHAY CRCW060310K0FKEA
19 2 R18, R32 RES, 4.02k 1% 0603 VISHAY CRCW06034K02FKEA
20 2 R19, R34 RES, 11k 1% 0603 VISHAY CRCW06011K0FKEA
21 1 R21 RES, 40.2k 1%, 0603 VISHAY CRCW060340K2FKEA
22 2 R27, R25 RES, 2.2Ω 1% 0603 VISHAY CRCW06032R20FKEA
23 1 R28 RES, 137k 1% 0603 VISHAY CRCW0603137KFKEA
24 1 R31 RES, 17.4k 1% 0603 VISHAY CRCW06017K4FKEA
25 2 R42, R43 RES, 10Ω 1% 0603 VISHAY CRCW060310R0FKEA
26 9 R8, R11, R16, R35, R39, R48, R55, R20, R36,
R30, R26
RES, 0Ω 0603 VISHAY CRCW06030000Z0EA
27 2 RS1, RS2 RES, 0.000Ω 1W 1% 2512 TEPRO RN5326
28 1 U1 LTC3838 38-LEAD TSSOP LINEAR TECH. LTC3838EFE
Additional Circuit Components
1 0 C1, C2, C15, C17 CAP, 0603 OPTIONAL
2 0 CIN6-CIN8 CAP, 1210 OPTIONAL
3 0 COUT13-COUT16 CAP, 7343 OPTIONAL
4 0 Q5-Q8 MOSFET, N-CHANNEL LFPAK OPTIONAL
5 0 R1, R4, R7, R9, R47, R14, R15, R24, R29, R41,
R45, R3, R6, R10, R37, R44, R49, R50
RES, 0603 OPTIONAL
6 2 Q9, Q10 MOSFET, N-CHANNEL DPAK VISHAY SUD50N03-12P-E3
7 2 R51, R52 RES, 10k 1% 0603 VISHAY CRCW060310K0FKEA
8 2 R53, R54 RES, 0.01Ω 1/2W 1% 2010 VISHAY WSL2010R0100FEA
PARTS LIST

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DEMO MANUAL DC1626A
1626A-A (DCR Sense)
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Hardware/Components (For Demo Board Only)
1 4 STAND-OFF STAND-OFF, NYLON 0.25" KEYSTONE 8831 (SNAP ON)
2 23 E1-E12, E14-E25 TESTPOINT, TURRET 0.095" MILL-MAX 2501-2-00-80-00-00-07-0
3 6 J1-J6 JACK, BANANA KEYSTONE 575-4
4 2 J7, J8 CONN, BNC 5PINS CONNEX 112404
5 2 JP1, JP4 2MM SINGLE ROW HEADER, 3-PIN SAMTEC TMM-103-02-L-S
6 4 JP1-JP4 SHUNT SAMTEC 2SN-BK-G
7 2 JP2, JP3 2MM SINGLE ROW HEADER, 4-PIN SAMTEC TMM-104-02-L-S
PARTS LIST
1626A-B (RSENSE)
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
11C12 CAP, X7R 330pF 50V 0603 AVX 06035C331KAT2A
2 2 C3, C16 CAP, X7R 1000pF 16V 0603 AVX 0603YC102KAT2A
3 3 C4, C10, C13 CAP, X5R 0.1μF 50V 0603 AVX 06035D104KAT2A
4 2 C5, C14 CAP, X5R 0.01μF 25V 0603 AAC 0603D103KAT2A
5 2 C6, C11 CAP, NPO 47pF 16V 0603 AVX 0603YA470KAT4A
6 1 C7 CAP, NPO 220pF 25V 0603 AVX 06033A221KAT2A
7 1 C8 CAP, X5R 4.7μF 16V 0805 AVX 0805YD475KAT2A
8 2 C9, C18 CAP, X5R 1μF 16V 0603 AVX 0603YD105KAT2A
9 2 CIN1, CIN2 CAP, 100μF 35V SIZE-F SUNCON 35HVH100M
10 3 CIN3, CIN4, CIN5 CAP, X5R 10μF 35V 1210 TAIYO YUDEN GMK325BJ106MN-T
11 4 COUT1, COUT2, COUT5, COUT6 CAP, 330μF 2.5V SIZE 7343 SANYO 2R5TPE330M9
12 4 COUT3, COUT4, COUT7, COUT8 CAP, X5R 100μF 6.3V 1206 MURATA GRM31CR60J107ME39L
13 2 D1, D2 DIODE, SCHOTTKY SOD-323 CENTRAL SEMI. CMDSH-4ETR
14 2 L1, L2 IND, 0.68μH WURTH 7443330068
15 2 Q1, Q3 MOSFET, N-CHANNEL LFPAK RENESAS RJK0305DPB-00-J0
16 2 Q2, Q4 MOSFET, N-CHANNEL LFPAK RENESAS RJK0330DPB-00-J0
17 2 R12, R38 RES, 100k 1% 0603 VISHAY CRCW0603100KFKEA
18 1 R13 RES, 15k 1% 0603 VISHAY CRCW060315K0FKEA
19 4 R14, R15, R41, R45 RES, 10Ω 1% 0603 VISHAY CRCW060310R0FKEA
20 4 R17, R23, R40, R46 RES, 10k 1% 0603 VISHAY CRCW060310K0FKEA
21 1 R21 RES, 45.3k 1% 0603 VISHAY CRCW060345K3FKEA
22 2 R27, R25 RES, 2.2Ω 1% 0603 VISHAY CRCW06032R20FKEA
23 1 R28 RES, 137k 1% 0603 VISHAY CRCW0603137KFKEA
24 1 R31 RES, 20k 1% 0603 VISHAY CRCW060320K0FKEA
25 2 R42, R43 RES, 10Ω 1% 0603 VISHAY CRCW060310R0FKEA
26 9 R8, R11, R16, R35, R39, R48, R55, R24, R29 RES, 0Ω 0603 VISHAY CRCW06030000Z0EA
27 2 RS1, RS2 RES, SENSE 0.0025 2512 VISHAY WSL25122L500FEA
28 1 U1 LTC3838 38-LEAD TSSOP LINEAR TECH. LTC3838EFE

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DEMO MANUAL DC1626A
PARTS LIST
1626A-B (RSENSE)
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Additional Circuit Components
1 0 C1, C2, C15, C17 CAP, 0603 OPTIONAL
2 0 CIN6-CIN8 CAP, 1210 OPTIONAL
3 0 COUT13-COUT16 CAP, 7343 OPTIONAL
4 0 Q5-Q8 MOSFET, N-CHANNEL LFPAK OPTIONAL
5 2 Q9, Q10 SUD50N03-12P-E3 VISHAY SUD50N03-12P-E3
6 0 R1, R4, R7, R9, R47, R18, R19, R20, R32, R34,
R20, R36, R3, R6, R10, R37, R44, R49, R50,
R30, R26
RES, 0603 OPTIONAL
7 2 R51, R52 RES, 10k 1% 0603 VISHAY CRCW060310K0FKEA
8 2 R53, R54 RES, 0.01Ω 1/2W 1% 2010 VISHAY WSL2010R0100FEA
Hardware/Components (For Demo Board Only)
1 4 STAND-OFF STAND-OFF, NYLON 0.25" KEYSTONE, 8831 (SNAP ON)
2 23 E1-E12, E14-E25 TESTPOINT, TURRET 0.095" MILL-MAX 2501-2-00-80-00-00-07-0
3 6 J1-J6 JACK, BANANA KEYSTONE 575-4
4 2 J7, J8 CONN, BNC 5-PINS CONNEX 112404
5 2 JP1, JP4 2MM SINGLE ROW HEADER, 3-PIN SAMTEC TMM-103-02-L-S
6 4 JP1-JP4 SHUNT SAMTEC 2SN-BK-G
7 2 JP2, JP3 2MM SINGLE ROW HEADER, 4PIN SAMTEC TMM-104-02-L-S

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DEMO MANUAL DC1626A
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
CC
B B A A
1.5V / 15A
DCR SENSE FILTER / DIVIDER FOR PHASE 2
FSW =300kHz
4.5V - 26V
OFF
ON
RUN2
OFF
RUN1
ON
DCR SENSE FILTER / DIVIDER FOR PHASE 1
1.2V / 15A
NOTE:
TIE SGND PIN TO PGND PAD UNDERNEATH IC.
FCM
DCM
SYNC
60 DEG
90 DEG
120 DEG
CLKOUT
OPTIONAL COMPONENTS FOR SINGLE
OUTPUT, DUAL PHASE OPERATION
10mV / A
LOAD STEP CIRCUIT #1
IOSTEP1+
LOAD STEP 5% DUTY CYCLE MAX
VOUT1
LOAD STEP 10mV / A
LOAD STEP CIRCUIT #2
IOSTEP2+
5% DUTY CYCLE MAX
VOUT2
ALL CAPACITORS ARE IN MICROFARADS, 0603.
ASSY L1,L2
NOTES: UNLESS OTHERWISE SPECIFIED
1. ALL RESISTORS ARE IN OHMS, 0603.
-A (DCR SENSE)
2. INSTALL SHUNTS ON JUMPERS AS SHOWN.
-B (RSENSE) Vishay IHLP4040DZ-01 0.56uH
WURTH 7443330068(0.68uH)
C16, C3
0.1uF
1000pF
R32, R18
4.02K
OPT
R34,R19
11K
OPT 0
OPT
R36,R20 R41,R45,
OPT
10 0.000 Ohm 2512
RS1, RS2
0.0025 Ohm 2512
OPTIONAL COUT ONLY ADD FOOTPRINTS ON SOLDERMASK, DO NOT SHOW IN SCHEMATIC.
PHASMD
MODE
-2PETSOI-1PETSOI
2512 2512
R29,R24 R30,R26 R31 R21
R14,R15,
OPT
00
OPT 17.4K
20K 40.2K
45.3K
NOTE: EXTERNALLY TIE THE
DTR1 PIN TO THE DTR2 PIN
IF THE TRANSIENT DETECT
CIRCUIT IS USED
MIKE S.PRODUCTION 11-11-52
__
REVISION HISTORY
ETADNOITPIRCSED APPROVEDECO REV
2
Thursday, October 13, 2011
11
WIDE INPUT RANGE, HIGH EFFICIENCY DUALSTEP-DOWN DC-DC CONVERTER
HZ
MIKES.
N/A
LTC3838EFE
DEMO CIRCUIT 1626A
SIZE DATE:
.VER.ONCI
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY
Fax:[phone] Milpitas,CA95035
Phone:[phone]McCarthyBlvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TODESIGN 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 LINEARTECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
SW1
RUN1
RUN2
SW2
EXTVCC
VOUT2
S2+
S2-
VIN
INTVCC
EXTVCC
VIN
S1+
S1-
VOUT1
S2+
S2-
INTVCC
VFB2
TRK/SS2
VRNG2
VRNG1
S1+
S1-
TRK/SS1
TRK/SS2
VIN
INTVCC
TRK/SS1
VOUT2
INTVCC
INTVCC
INTVCC
VFB2 INTVCC
VRNG1 VRNG2
RUN1 RUN2
VOUT1 VOUT2
VOUT1
VOUT2
INTVCC
INTVCC
R15
*
R21
*
R14
*
R48 0
J4 GND
R12 100K
COUT3
100uF 6.3V 1206
R160
+
COUT5
330uF
7343-D15T
2.5V
R4 OPT
R20
*
CIN4 10uF
35V
1210
+
COUT1 330uF 7343-D15T 2.5V
C8 4.7uF 16V 0805
R50 OPT
CIN6
OPT
1210
E22
C16
*
+
COUT16 OPT
7343-D15T
R47 OPT
C14 0.01uF
E18PULSE2
R6 OPT
C3
*
E1
PGOOD2
E15
PGOOD1
J3 VOUT2
Q4
RJK0330DPB
2
4
5
3
1
JP2
1
2
3
4
R36
*
R350
L2
*
R45
*
R42 10
R30
*
+
COUT14
OPT
7343-D15T
Q8
OPT
2
4
5
3
1
U1
LTC3838EFE
1
2 3 4
6
7
29 30 31 33
8
9
10
32
34
35 36 37 38
39
5
11
12 13 14
15
16 17
18
19 20
21
22 23
24
25
26
27
28
DTR2 SENSE2- SENSE2+ VFB2 ITH2 VRNG2
PGND
INTVCC
EXTVCC
BG2
PHASEMD MODE/PLLIN CLKOUT
DRVCC2
SW2
TG2
BOOST2
PGOOD2
RUN2
PGND
TRACK/SS2 SGND RT VRNG1 ITH1 TRACK/SS1 VOUTSENSE1+ VOUTSENSE1- SENSE1+
1RTD-1ESNES
RUN1
PGOOD1
BOOST1
TG1
SW1
BG1
DRVCC1
VIN
JP1
13
2
J6 GND
R27 2.2
E9
CLKOUT
+
CIN1
100uF
35V
35HV100M
R17 10K
JP4
13
2
Q6
OPT
2
4
5
3
1
R7 OPT
J7 1
2
3
4
5
C9 1uF
R53 0.01 2010
J5 VOUT1
COUT8 100uF 6.3V 1206
RS1
*
COUT7
100uF 6.3V 1206
E16
EXTVCC
R29
*
R41
*
+
COUT6
330uF
7343-D15T
2.5V
C7 220pF
Q5
OPT
2
4
5
3
1
R55 0
CIN3 10uF 35V 1210
D2 CMDSH-3
+
OPT
7343-D15T
COUT13
E17PULSE1
E10
TRK/SS1
E24
C12 330pF
R1 OPT
R24
*
E19
GND
+
COUT2 330uF 7343-D15T 2.5V
E6 VO2+
J8 1
2
3
4
5
R26
*
R34
*
C18 1uF
R19
*
R23 10K
CIN5 10uF
1210
35V
C10 0.1uF
C15 OPT
E5 VIN-
Q3
RJK0305DPB
2
4
5
3
1
C5 0.01uF
R13 15K
D1
CMDSH-3
E7 VO2-
J1 VIN
R32
*
R44 OPT
Q10 SUD50N03-12P
3
1
2
C2 OPT
R18
*
E23
E21 GND
C6 47pF
R46 10K
C11 47pF
E20 GND
R37 OPT
+
CIN2 100uF 35V
35HV100M
R10 OPT
E11VO1_SNS+
J2 GND
R51 10K
CIN8
(OPT)
1210
C13 0.1uF
C4 0.1uF
R8 0
JP3
1
2
3
4
R39 0 R40
10K
R11 0
Q1
RJK0305DPB
2
4
5
3
1
C17 OPT
R49 OPT
RS2
*
E2
RUN2
Q9 SUD50N03-12P
3
1
2
E3 VIN+
CIN7
(OPT)
1210
COUT4 100uF 6.3V 1206
L1
*
R38 100K
E8
PLLIN
E12VO1_SNS-
Q7
OPT
2
4
5
3
1
Q2
RJK0330DPB
2
4
5
3
1
R31
*
E4
TRK/SS2
R25
2.2
R28 137K
R54 0.01 2010
R43 10
E25
R9 OPT
R52 10K
E14
RUN1
R3 OPT
C1 OPT
+
COUT15
OPT
7343-D15T

10
dc1626afa
DEMO MANUAL DC1626A
LinearTechnology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ●FAX: [phone] ●www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2011
LT 1011 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