Linear Technology DC1905A Quick setup guide

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DEMO MANUAL DC1905A
Description
LTM4633
High Efficiency, Triple 10A
Step-Down µModule Regulator
Demonstrationcircuit DC1905AfeaturestheLT M
®
4633EY,
a high efficiency, triple 10A step-down power µModule
®
regulator. The input voltage range is from 4.7V to 16V with
commoninputsource,or2.375Vto16Vwithanexternalbias
supply.Theoutputvoltagerangeis0.8Vto1.8VforChannel1
and Channel 2, 0.8V to 5.5V for Channel 3. Derating is
necessary forcertain VIN,VOUT,frequency and thermal con-
ditions. The DC1905A offers access to the TRACK/SS pins
allowing the user to program output tracking or soft-start
period.Theboard operates in continuous conduction mode
in heavy load conditions. For high efficiency at low load L, LT, LTC, LTM, Burst Mode, µModule, Linear Technology and the Linear logo are registered
trademarks of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
BoarD photo
currents, the MODE jumper (JP4) selects pulse-skipping
mode for noise sensitive applications or Burst-Mode
®
operation in less noise sensitive applications. Channel 1
and 2 can be connected in parallel for a single 20A output
solutionwith optional jumperresistors. The LTM4633 data
sheet must be read in conjunction with this demo manual
prior to working on or modifying demo circuit DC1905A.
Design files for this circuit board are available at
http://www.linear.com/demo/DC1905A

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DEMO MANUAL DC1905A
Quick start proceDure
Demonstration circuit DC1905A is an easy way to evalu-
ate the performance of the LTM4633EY. 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
application:
RUN1 RUN2 RUN3 MODE
ON ON ON CCM
2. With power off, connect the input power supply, loads
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
voltage of channel 1 should be 1.0V±1.5% (0.985V
to 1.015V). The output voltage of channel 2 should be
1.2V ±1.5% (1.182V to 1.218V). The output voltage of
channel 3 should be 3.3V ±1.5% (3.25V to 3.349V).
4. Vary the input voltage from 4.7V to 16V and adjust the
load current of each channel from 0A to 10A. Observe
the output voltage regulation, ripple voltage, efficiency,
and other parameters.
5. (Optional) For optional load transient test, apply an
adjustable pulse signal between IOSTEP_CLK and GND
test points. The pulse amplitude sets the load step cur-
rent amplitude. Keep the pulse width short (<1ms) and
pulse duty cycle low (<5%) to limit the thermal stress
on the load transient circuit. Switch the jumper resistors
R30, R31 or R34 (on the backside of boards) to apply
load transient on channel 1, channel 2, or channel 3
respectively.
6. (Optional) LTM4633 can be synchronized to an external
clock signal. Place the JP4 jumper on EXT_CLK and
apply a clock signal (0V to 5V, square wave) on the
CLKIN test point.
7. (Optional) The outputs of LTM4633 can track another
supply. If tracking external voltage is selected, the cor-
respondingtestpoints, TRACK1, TRACK2, and TRACK3,
need to be connected to a valid voltage signal.
8. (Optional) Channel 1 and 2 can be connected in paral-
lel for a 20A polyphase operation on DC1905A. Install
0Ω resistors on R32, R33, R35, R36 and remove R15.
Output voltage is set by R4 based on equation VOUT =
0.8V (1 + 60.4k/2/R4).
performance summary
Specifications are at TA= 25°C
PARAMETER CONDITIONS VALUE
Input Voltage Range 4.7V to 16V
Output Voltages 1.0V, 1.2V, 3.3V ±1.5%
Maximum Continuous Output Current Derating Is Necessary for Certain Operating Conditions.
See Data Sheet for Details
10ADC for Each Channel
Operating Frequency 750kHz
Efficiency of Channel 1 VIN = 12V, VOUT1 = 1.0V, IOUT1 = 10A 77% See Figure 2
Efficiency of Channel 2 VIN = 12V, VOUT2 = 1.2V, IOUT2 = 10A 81% See Figure 3
Efficiency of Channel 3 VIN = 12V, VOUT3 = 3.3V, IOUT3 = 10A 91% See Figure 4
Load Transient of Channel 1 VIN = 12V, VOUT1 = 1.0V, ISTEP = 0A to 5A See Figure 5
Load Transient of Channel 2 VIN = 12V, VOUT2 = 1.2V, ISTEP = 0A to 5A See Figure 6
Load Transient of Channel 3 VIN = 12V, VOUT3 = 3.3V, ISTEP = 0A to 5A See Figure 7

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DEMO MANUAL DC1905A
Quick start proceDure
–
+
–
+
LOAD LOAD LOAD
–+
–+
–+
VIN
dc1905a F01
+
+–
+
+–
+
+–
+
Figure 1. Measurement Setup of DC1905A

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DEMO MANUAL DC1905A
Figure 2. Measured Efficiency on Channel 1. VOUT1 = 1.0V,
fSW = 750kHz, CCM, Channel 2, 3 Disabled
DC1905A Efficiency (LTM4633) VOUT = 1.0V DC1905A Efficiency (LTM4633) VOUT = 1.2V
DC1905A Efficiency (LTM4633) VOUT =3.3V
Figure 3. Measured Efficiency on Channel 2. VOUT2 = 1.2V,
fSW = 750kHz, CCM, Channel 1, 3 Disabled
Figure 4. Measured Efficiency on Channel 3. VOUT3 = 3.3V,
fSW = 750kHz, CCM, Channel 1, 2 Disabled
Quick start proceDure
LOAD CURRENT (A)
EFFICIENCY (%)
dc1905a F02
100
60
70
80
90
50
40
30
20
0
10
1086420
VIN = 16V
VIN = 12V
VIN = 8V
VIN = 5V
LOAD CURRENT (A)
EFFICIENCY (%)
dc1905a F03
100
60
70
80
90
50
40
30
20
0
10
1086420
VIN = 16V
VIN = 12V
VIN = 8V
VIN = 5V
LOAD CURRENT (A)
EFFICIENCY (%)
dc1905a F04
100
60
70
80
90
50
40
30
20
0
10
1086420
VIN = 16V
VIN = 12V
VIN = 8V
VIN = 5V

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DEMO MANUAL DC1905A
Quick start proceDure
Figure 6. Measured Channel 2 Load Transient
VIN = 12V, VOUT1 = 1.2V, ISTEP = 0A to 5A, di/dt = 5A/µs
VOUT = 100mV/DIV
IOUT_STEP = 5A/DIV
dc1905a F06
Figure 5. Measured Channel 1 Load Transient
VIN = 12V, VOUT1 = 1.0V, ISTEP = 0A to 5A, di/dt = 5A/µs
VOUT = 100mV/DIV
IOUT_STEP = 5A/DIV
dc1905a F05

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DEMO MANUAL DC1905A
Quick start proceDure
Figure 8. Thermal Image of LTM4633
VIN = 12V, VOUT1 = 1.0V, ILOAD1 = 10A,
VOUT2 = 1.2V, ILOAD2 = 10A, VOUT3 = 3.3V, ILOAD3 = 2A
Ambient Temperature= 21.6°C, No Forced Air Flow
Figure 9. Thermal Image of LTM4633
VIN = 12V, VOUT1 = 1.0V, ILOAD1 = 10A,
VOUT2 = 1.2V, ILOAD2 = 10A, VOUT3 = 3.3V, ILOAD3 = 5A
Ambient Temperature= 21.6°C, No Forced Air Flow
Figure 7. Measured Channel 3 Load Transient
VIN = 12V, VOUT3 = 3.3V, ISTEP = 0A to 5A
VOUT = 200mV/DIV
IOUT_STEP = 5A/DIV
dc1905a F07

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DEMO MANUAL DC1905A
parts List
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 1 U1 LTM4633EY#PBF, BGA-15 × 15-144P LINEAR TECH., LTM4633EY#PBF
2 1 CIN1 Cap., 150µF, 25V, Aluminum Electr., SUN ELECT., 25CE150AX
3 3 CIN2, CIN3, CIN5 Cap., X5R, 22µF, 25V, 10%,1210 MURATA, GRM32ER61E226KE15L
4 1 C5 Cap., X5R, 4.7µF, 10V,10%, 0603 AVX, 0603ZD475KAT2A
5 1 C4 Cap., X7R, 1µF, 10V,10%, 0603 AVX, 0603ZC105KAT2A
6 3 COUT1, COUT5, COUT12 Cap., 470µF, 4V, POSCAP, F8 SANYO, 4TPE470MCL
7 3 COUT4, COUT7, COUT9 Cap., X5R, 100µF, 6.3V, 20%, 1210 AVX, 12106D107MAT2A
8 3 C1, C6, C9 CAP., 220pF, 10%, 50V, NPO 0603 AVX, 06035A221KAT
9 3 C12, C13, C14 Cap., X5R, 0.1µF,25V, 10%, 0603 AVX, 06033D104KAT2A
10 4 R1, R6, R14, R16, R17, R19 Res., Chip, 10, 1%, 0603 VISHAY, CRCW060310R0FKEA
11 1 R4 Res., Chip, 243k, 1%, 0603 VISHAY, CRCW0603243K0FKEA
12 4 R8, R9, R18, R21 Res., Chip, 10k, 1%, 0603 VISHAY, CRCW060310K0FKEA
13 1 R15 Res., Chip, 121k, 1%, 0603 VISHAY, CRCW0603121K0FKEA
14 1 R20 Res., Chip, 19.1k, 1%, 0603 VISHAY, CRCW060319K1FKEA
Additional Demo Board Circuit Components
1 2 C18, C19 Cap., X7R, 1µF, 10V,10%, 0603 AVX, 0603ZC105KAT2A
2 0 COUT2, COUT3, COUT6, COUT8,
COUT10, COUT11
1210 OPT
3 0 C2, C3, C7, C8, C10, C11 0603 OPT
4 3 C15, C16, C17 CAP., X7R, 0.01µF, 50V, 10%, 0603 AVX, 06035C103KAT2A
5 1 Q1 N-Channel 30-V MOSFET VISHAY, SUD50N03-09P-GE3
6 3 R2, R10, R12 Res., Chip, 23.2k, 1%, 0603 VISHAY, CRCW060323K2FKEA
7 2 R5, R30 Res., Chip, 0Ω, 0.5W, 2010 TEPRO,RN6083
8 1 R7 Res., Chip, 0Ω, 1%, 0805 VISHAY, CRCW08050000Z0ED
9 1 R37 Res., Chip, 10k, 1%, 0603 VISHAY, CRCW060310K0FKEA
10 4 R22, R24, R26, R28 Res., Chip, 0Ω, 1%, 0603 VISHAY, CRCW06030000Z0EA
11 0 R31, R34 2010 OPT
12 1 R38 Res., Chip, 0.01Ω, 2W, 2512 VISHAY, WSL2512R0100FEA
13 0 R39 2512 OPT
14 0 R3, R11, R13, R23, R25, R27, R29,
R32, R33, R35, R36
0603 OPT
15 0 CIN4 1210 OPT
Hardware: For Demo Board Only
1 20 E1-E20 TESTPOINT, TURRET, .094" PBF MILL-MAX, 2501-2-00-80-00-00-07-0
2 3 JP1, JP2, JP3 HEADER 3 PIN, 0.079 SINGLE ROW SAMTEC, TMM103-02-L-S
3 1 JP4 HEADER 8 PIN, 0.079 DOUBLE ROW SAMTEC, TMM104-02-L-D
4 1 JP5 HEADER 2 PIN, 0.079 SINGLE ROW SAMTEC, TMM102-02-L-S
5 8 J1-J8 JACK BANANA KEYSTONE, 575-4
6 4 XJP1-XJP4 SHUNT, .079" CENTER SAMTEC, 2SN-BK-G
7 4 (STAND-OFF) STAND-OFF, NYLON, 0.50" KEYSTONE, 8833(SNAP ON)

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DEMO MANUAL DC1905A
schematic Diagram

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DEMO MANUAL DC1905A
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

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DEMO MANUAL DC1905A
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ●FAX: [phone] ●www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2013
LT 0713 • PRINTED IN USA
DEMONSTRATION BOARD IMPORTANT NOTICE
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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 LT C 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
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This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LT C applica-
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