Linear Technology DC1723A Quick setup guide

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DEMO MANUAL DC1723A
DESCRIPTION
LTM8050
58VIN, 2A Step-Down
µModule Regulator
DemocircuitDC1723Afeatures the LT M
®
8050,aμModule
®
(micromodule) step-down converter that can deliver up to
2A of output current. DC1723A is designed for a 5V, 2A
output from a 7.5V to 58V input at 400kHz. The wide input
range of the LTM8050 allows a variety of input sources
such as automotive batteries and industrial supplies. At
light loads, the LTM8050 enters Burst Mode
®
operation
to maintain high efficiency and low output ripple over a
broad current range. The user adjustable features of the
LTM8050 such as output voltage, switching frequency,
soft-start, and power good can be changed on DC1723A
L, LT, LTC, LTM, Linear Technology, the Linear logo, µModule and Burst Mode are registered
trademarks of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
PERFORMANCE SUMMARY
BOARD PHOTO
simply by modifying or installing the appropriate resistors
and/or capacitors.
The LTM8050 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 the demo circuit 1723A.
Design files for this circuit board are available at
http://www.linear.com/demo
Specifications are at TA= 25°C
PARAMETER CONDITIONS MIN TYP MAX UNITS
Minimum Input Voltage, VIN VOUT = 5V 7.5 V
Maximum Input Voltage, VIN VOUT = 5V 58 V
Output Voltage, VOUT R4 = 93.1k 4.87 5.02 5.17 V
Maximum Output Current 2 A
Switching Frequency R6 = 97.6k 400 kHz
Efficiency VIN = 12V, IOUT = 2A 85 %

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DEMO MANUAL DC1723A
QUICK START PROCEDURE
Demonstration circuit 1723A is easy to set up to evalu-
ate the performance of the LTM8050. 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
rippleby
touchingthe probe tip directly acrosstheterminals
of the input or output capacitors. See Figure 2 for proper
scope probe technique.
1. Place JP1 in the ON position.
2. With power off, connect the input power supply to VIN
and GND.
3. Turn on the power at the input.
Note:Makesurethatthe input voltage does not exceed 58V.
4. Check for the proper output voltage.
Note: If there is no output, temporarily disconnect the load
to make sure that the load is not set too high or is shorted.
5. Once the proper output voltage is established, adjust
the loads within the operating range and observe the
output voltage regulation, ripple voltage, efficiency and
other parameters.
Figure 1. Measurement Equipment Setup

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DEMO MANUAL DC1723A
QUICK START PROCEDURE
Figure 2. Measuring Input or Output Ripple
FREQUENCY (MHz)
0
–140
INTENSITY (dBm)
–120
–80
–60
–40
0
0.5 2.5 3.5
DC1723A F03
–100
–20
24.5 5
11.5 3 4
Figure 3. DC1723A Output Noise Spectrum (VIN = 12V, VOUT = 5V, IOUT = 2A)
GNDVIN OR VOUT DC1723A F02

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DEMO MANUAL DC1723A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 2 C2, C9 CAP., X7R, 2.2µF, 100V, 10%, 1206 MURATA, GRM31CR72A225KA73
2 1 C3 CAP., X5R, 100µF, 6.3V, 20%, 1210 MURATA, GRM32ER60J107ME20L
3 1 C10 CAP., X7R, 0.1µF, 10V, 10%, 0603 AVX, 0603ZC104KAT2A
4 1 R2 RES., CHIP, 0Ω, 1/10W, 0603 NIC, NRC06ZOTRF
5 1 R4 RES., CHIP, 93.1k, 1/10W, 1% 0603 VISHAY, CRCW060393K1FKEA
6 1 R5 RES., CHIP, 100k, 1/10W, 1% 0603 NIC, NRC06F1003TRF
7 1 R6 RES., CHIP, 97.6k, 1/10W, 1% 0603 VISHAY, CRCW060397K6FKEA
8 1 R7 RES., CHIP, 0Ω, 1/4W, 1% 1206 NIC, NRC12Z0TRF
9 1 U1 IC., MODULE REGULATOR, LTM8050EY BGA-70 LEAD LINEAR TECH., LTM8050EY
Additional Demo Board Circuit Components
1 1 C1 CAP., ELECTROLYTIC, 10µF, 100V SUN ELECT., 100CE10BS
2 0 C4, C5, C8 (OPT) CAP., 0603
3 0 C6 (OPT.) CAP., 1210
4 0 C7 (OPT.) CAP., ALUM CAP.,
5 0 R1, R3 (OPT.) RES., CHIP, 0603
6 0 FB1 (OPT.) FERRITE BEAD, M TYPE TAIYO YUDEN, FBMJ3216HS800T
7 0 L1 (OPT.) IND., 10µH VISHAY, IHLP-2525CZ-01
Hardware-For Demo Board Only
1 8 E1-E8 TESTPOINT, TURRET, 0.094" PBF MILL-MAX, 2501-2-00-80-00-00-07-0
2 2 JP1-JP2 3 PIN 0.079" SINGLE ROW HEADER SULLINS, NRPN031PAEN-RC
3 1 XJP1-XJP2 SHUNT, 0.079" CENTER SAMTEC, 2SN-BK-G
4 1 Stencil

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DEMO MANUAL DC1723A
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 DC1723A
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ●FAX: [phone] ●www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2013
LT 0513 • PRINTED IN USA
DEMONSTRATION BOARD IMPORTANT NOTICE
Linear Technology Corporation (LT C ) 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 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
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 LT C 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. LT C assumes no liability for applications assistance,
customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind.
LT C 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 LT C applica-
tion engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation

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