Linear Technology LT3507 Quick setup guide

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DEMO MANUAL DC1161B
DESCRIPTION
LT3507
Triple Monolithic Step-Down
Regulator with LDO
Demo circuit 1161B is a triple monolithic step-down
regulator with LDO featuring LT
®
3507. The demo circuit
is designed for 1.8V, 3.3V, 5.0V and 2.5V outputs from a
7V to 36V input. The current capability of each channel
is 2.4A, 1.3A, 1.4A and 0.2A respectively. Independent
input voltage, feedback, soft-start and power good pins
for each channel simplify complex power supply tracking/
sequencing requirements.
All three converters are either synchronized to a common
external clock input or single-resistor programmable from
250kHz to 2.5MHz using internal oscillator. At all frequen-
cies, a 180° phase shift between VOUT1 and the other two
outputs is maintained, reducing input voltage ripple and
component size. Programmable frequency allows for opti-
mization between efficiency and external component size.
L, LT, LTC, LTM, 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
Each output can be independently disabled using its own
soft-start pin, or by using the SHDN pin the entire part
can be placed in a low quiescent current shutdown mode.
The LT3507 data sheet gives a complete description of
the part, operation and application information. The data
sheet must be read in conjunction with this quick start
guide for demo circuit 1161B.
Design files for this circuit board are available at
http://www.linear.com/demo
(TA= 25°C)
PARAMETER CONDITION VALUE
Minimum Input Voltage 7V
Maximum Input Voltage 36V
Output Voltage VOUT1 V
IN = 7V ~ 36V 1.80V ±3%
Output Voltage VOUT2 VIN = 7V ~ 36V 3.33V ±3%
Output Voltage VOUT3 VIN = 7V ~ 36V 5.0V ±3%
Output Voltage VOUT4 VIN = 7V ~ 36V 2.52V ±3%
Switching Frequency 450kHz ±10%
Maximum Output Current IOUT1 VIN = 7V ~ 36V 2.4A
Maximum Output Current IOUT2 VIN = 7V ~ 36V 1.3A
Maximum Output Current IOUT3 VIN = 7V ~ 36V 1.4A
Maximum Output Current IOUT4 VIN = 7V ~ 36V 0.2A
Voltage Ripple VOUT1 VIN = 12V, IOUT1 = 2.4A <20mV
Voltage Ripple VOUT2 VIN = 12V, IOUT2= 1.3A <20mV
Voltage Ripple VOUT3 VIN = 12V, IOUT3= 1.4A <20mV
Voltage Ripple VOUT4 VIN = 12V, IOUT4= 0.2A <10mV
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DEMO MANUAL DC1161B
QUICK START PROCEDURE
Figure 1. DC1161B Proper Equipment Setup
Figure 2. Measuring Input or Output Ripple
Demo circuit 1161B is easy to set up to evaluate the
performance of the LT3507. Refer to Figure 1 for proper
measurement equipment setup and follow the procedure
below:
Note: When measuring the input or output voltage ripple,
care must be taken to avoid a long ground lead on the
oscilloscope probe. Measure the input or output voltage
ripple by touching the probe tip directly across the VIN or
VOUT and GND terminals. See Figure 2 for proper scope
probe technique.
1. With power off, connect the input power supply to VIN
and GND.
2. Turn on the power at the input.
Note: Make sure that the input voltage does not exceed 36V.
3. Check for the proper output voltages.
Note: If there is no output, temporarily disconnect the load
to make sure that the load is not set too high.
4. Once the proper output voltages are established, adjust
the load within the operating range and observe the
output voltage regulation, ripple voltage, efficiency and
other parameters.
A
–
+
V
+–
LOAD +
–
A
+
–
V
–+
LOAD –
+
A
+–
V
–
+V
–
+
LOAD
–
+
A
–+A
–+
V
+
–
LOAD
+
–
+
–
DC1161B F01
POWER
SUPPLY
VIN GND
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DEMO MANUAL DC1161B
SYNC FUNCTION EMI FILTER
Install a 10k R20 resistor if the board is synchronized from
an external signal generator.
Install EMI filters on the backside of the DC1161, however,
a trace cut is required for the insertion of the option circuit.
See Figure 3 for the cut line.
CUT HERE
Figure 3. Cut Line for the EMI Filter Installation
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DEMO MANUAL DC1161B
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER / PART #
Required Circuit Components
1 3 CIN1, CIN2, CIN3 CAP., X7R, 2.2μF, 50V, 10%, 1210 TDK, C3225X7R1H225K
2 3 C1, C2, C9 CAP., X7R, 0.22μF, 25V, 10%, 0603 TDK, C1608X7R1E224K
3 2 C3, C10 CAP., X5R, 47μF, 10V, 20%, 1206 TAIYO YUDEN, LMK316BJ476ML-T
4 1 C4 CAP., X5R, 22μF, 6.3V, 20%, 1206 TAIYO YUDEN, JMK316BJ226ML
5 3 C5, C6, C11 CAP., X7R, 680pF, 50V, 10%, 0402 AVX, 04025C681KAT
6 4 C7, C8, C13, C20 CAP., X5R, 0.1μF, 10V, 10%, 0402 AVX, 0402ZD104KAT
7 1 C12 CAP., X5R, 2.2μF, 6.3V, 20%, 0603 TAIYO YUDEN, JMK107BJ225MA
8 3 C15, C17, C19 CAP., NPO, 47pF, 50V, 5%, 0402 AVX, 04025A470JAT
9 1 D4 DIODE, SCHOTTKY, B340A, SMA-DIODE DIODES INC., B340A
10 2 D6, D5 DIODE, SCHOTTKY, B240A, SMA-DIODE DIODES INC., B240A
11 3 D7, D8, D9 DIODE, SCHOTTKY, CMDSH-4E, SOD323 CENTRAL SEMI., CMDSH-4E
12 1 L1 IND., 4.7μH NIC, NPIM74C4R7MTRF
13 1 L2 IND., 8.2μH NIC, NPIM74C8R2MTRF
14 1 L3 IND., 10μH NIC, NPIM74C100MTRF
15 1 Q1 XTOR, NPN, 50V LOW SATURATION, MLP322 ZETEX, ZXTCM322TA
16 5 R1, R2, R3, R15, R22 RES., CHIP, 100k, 1/16W, 1%, 0402 YAGEO, RC0402FR-07100KL
17 1 R4 RES., CHIP, 12.4k, 1/16W, 1%, 0402 VISHAY, CRCW040212K4FKEA
18 1 R5 RES., CHIP, 31.6k, 1/16W, 1% 0402 VISHAY, CRCW040231K6FKEA
19 3 R6, R7, R11 RES., CHIP, 20k, 1/16W, 1% 0402 VISHAY, CRCW040220K0FKEA
20 3 R8, R9, R23 RES., CHIP, 10k, 1/16W, 1% 0402 YAGEO, RC0402FR-0710KL
21 1 R10 RES., CHIP, 53.6k, 1/16W, 1% 0402 VISHAY, CRCW040253K6FKEA
22 1 R12 RES., CHIP, 10.2k, 1/16W, 1% 0402 NIC, NRC04F1022TRF
23 1 R13 RES., CHIP, 1.07k, 1/16W, 1% 0402 YAGEO, RC0402FR-071K07L
24 1 R14 RES., CHIP, 49.9k, 1/16W, 1% 0402 VISHAY, CRCW040249K9FKEA
25 1 R16 RES., CHIP, 499Ω, 1/16W, 1% 0402 AAC, CR05-4990FM
26 1 R17 RES., CHIP, 18.2k, 1/16W, 1% 0402 VISHAY, CRCW040218K2FKEA
27 1 R18 RES., CHIP, 3.32k, 1/16W, 1% 0402 VISHAY, CRCW04023K32FKEA
28 1 R19 RES., CHIP, 107k, 1/16W, 1% 0402 AAC, CR05-1073FM
29 1 U1 I.C., LT3507EUHF, QFN38UHF LINEAR TECH., LT3507EUHF
Additional Demo Board Circuit Components
1 1 CIN4 CAP., ELECTROLYTIC, 22μF, 50V SANYO, 50CE22LX
2 0 C14, C16, C18 CAP., 0402 OPT
3 0 C21 CAP., X7R, 0.01μF, 50V, 10%, 0603 OPT
4 0 C22 CAP., X7R, 2.2μF, 50V, 10%, 1210 OPT
5 0 C23 CAP., ELECTROLYTIC, 22μF 50V OPT
6 4 C24-C27 CAP., X5R, 1μF, 10V, 10%, 0603 MURATA, GRM188R61A105K
7 0 C28 CAP., 0402 OPT
8 0 C29 CAP., 1206 OPT
9 0 D1, D2, D3 DIODE, SCHOTTKY, CMDSH-4E, SOD323 OPT
10 0 FB1 BEAD, 1206 OPT TAIYO YUDEN, FB MJ3216HS800
11 0 L4 IND., 22μH, OPT VISHAY, IHLP4040DZER220-M01
12 0 R20 RES., CHIP, 0402 OPT
13 0 R21 RES., CHIP, 0603 OPT
Hardware-For Demo Board Only
1 10 E1, E2, E6-E9, E12-E15 TP, TURRET, 0.094" MILL-MAX, 2501-2-00-80-00-00-07-0
2 9 E3, E4, E5, E10, E11, E16-E19 TP, TURRET, 0.064" MILL-MAX, 2308-2-00-44
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DEMO MANUAL DC1161B
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 DC1161B
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ●FAX: [phone] ●www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2011
LT 0411 • 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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