DC2057A - Demo Manual

DEMO MANUAL DC2057A
LTC3638EMSE
High Efficiency, High VIN,
250mA Step-Down Converter
DESCRIPTION
Demonstration circuit 2057A is a high input voltage, 250mA
output DC/DC power supply featuring the LTC®3638. The
IC operates with high efficiency Burst Mode® operation
and includes an internal high side power MOSFET. The
board will accept an input voltage between 4V and 140V,
and provide jumper selected output voltages of 1.8V,
3.3V, 5V with an option for additional voltages. The IC
includes internal soft-start and a provision for increasing
soft-start time.
Included on the board is an ON/OFF jumper that can
also be configured as a precision undervoltage lockout.
Additional PC pads are included for programming current
limit to optimize efficiency and for reducing output voltage
ripple and reducing component size. A terminal (FBO)
is included to allow multiple boards to be paralleled for
higher output current.
PERFORMANCE SUMMARY
PARAMETER
Output voltages between 800mV and VIN can be programmed using optional resistors (higher voltage rating
output capacitors may be required).
The LTC3638 data sheet gives a complete description of the
IC operation and application information. The data sheet
must be read in conjunction with this quick start guide.
Design files for this circuit board are available at
http://www.linear.com/demo
L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks
of Linear Technology Corporation. All other trademarks are the property of their respective
owners.
Specifications are at TA = 25°C
CONDITION
Input Voltage Range
VALUE
4V to 140V
1.8V Output Voltage
VIN = 12V, IOUT = 0A to 250mA
1.8V ±2%
3.3V Output Voltage
VIN = 12V, IOUT = 0A to 250mA
3.3V ±2%
5V Output Voltage
VIN = 12V, IOUT = 0A to 250mA
5V ±2%
Maximum Output Current, IOUT
VIN = 4V to 140V, VOUT = 1.8V, 3.3V or 5V
250mA
Typical Efficiency
VIN = 12V, VOUT = 5V, IOUT = 250mA
83.7%
Typical Output Ripple
VIN = 140V, VOUT = 5V, IOUT = 100mA (20MHz BW) 81mVP-P
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DEMO MANUAL DC2057A
QUICK START PROCEDURE
Demonstration circuit 2057A is easy to set up to evaluate
the performance of the LTC3638. Refer to Figure 1 for
the proper measurement equipment setup and follow the
procedure below:
7.With power off, move jumpers JP1 and JP2 to the other
fixed voltage settings (1.8V or 3.3V). Repeat steps 5
and 6. Check for the proper output voltage and other
parameters.
1.With power off, connect the input power supply (set
for 0V) to VIN and GND (input return).
3.Connect the 5V output load between VOUT and GND
(Initial load: no load).
Note: When measuring the output or input voltage ripple,
do not use the long ground lead on the oscilloscope probe.
See Figure 2 for the proper scope probe technique. Short,
stiff leads need to be soldered to the (+) and (–) terminals
of an output capacitor. The probe’s ground ring needs to
touch the (–) lead and the probe tip needs to touch the
(+) lead.
4.Connect the DVMs to the input and outputs.
Additional Notes:
5.Turn on the input power supply and slowly increase to
12V. Check for the proper output voltages. (5V output
should be within 5V ±2%.)
1. CAUTION: Be careful when testing with high voltage.
High voltage can result in an electric shock if care
is not taken.
6.Once the proper output voltages are established, adjust
the loads within the operating range and observe the
output voltage regulation, ripple voltage and other
parameters.
2. For 5V output, VIN input voltage should be at least 5V
or higher.
2.Select 5V output using jumper JP1 (B position) and
JP2 (A position). Select ON position for JP3.
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DEMO MANUAL DC2057A
QUICK START PROCEDURE
Figure 1. Proper Measurement Equipment Setup
+
VOUT
COUT
–
GND
Figure 2. Measuring Output Voltage Ripple
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DEMO MANUAL DC2057A
QUICK START PROCEDURE
LTC3638 1.8VOUT Efficiency vs Load Current
LTC3638 3.3VOUT Efficiency vs Load Current
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DEMO MANUAL DC2057A
QUICK START PROCEDURE
LTC3638 5VOUT Efficiency vs Load Current
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DEMO MANUAL DC2057A
PARTS LIST
ITEM
QTY
REFERENCE
PART DESCRIPTION
1
2
MANUFACTURER/PART NUMBER
1
C1
CAP.SMD ALUM. ELECT., 22µF, 200V KE0-MVA NIPPON CHEMI-CON, EMVE201ARA220MKG5S
1
C2
CAP., X7R, 1µF, 200V, 10% 2220
KEMET, C2220X105K2RACTU
3
1
C4
CAP., X7R, 47nF, 25V, 10% 0603
AVX, 06033C473KAT2A
4
2
C6, C7
CAP., X7R, 100µF, 10V, 20% 1210
TAIYO YUDEN, LMK325ABJ107MMH-T
5
1
C9
CAP., X7R, 0.1µF, 25V, 10% 0603
AVX, 06033C104KAT2A
6
1
D1
DIODE, SBR1U200P1
DIODES, SBR1U200P1-7
7
1
L1
INDUCTOR, 150µH
SUMIDA, CDRH105R-151
8
1
R1
RES., CHIP, 2M, 1/16W, 5% 0603
VISHAY, CRCW06032M00JNEA
9
1
U1
IC., LTC3638EMSE MSE16(12), 4X3MM
LINEAR TECH., LTC3638EMSE
Additional Demo Board Circuit Components
10
0
C3 (OPT)
CAP., 0603
OPT
11
0
C8, C10 (OPT)
CAP., 1210
OPT
12
0
R2, R4, R7, R8 (OPT)
RES., 0603
OPT
13
2
R3, R6
RES., CHIP, 0Ω, 1/16W, 0603
VISHAY, CRCW06030000Z0EA
14
5
E1, E2, E3, E4, E5
TESTPOINT, TURRET 0.094"
MILLMAX 2501-2-00-80-00-00-07-0
15
3
JP1, JP2, JP3
JMP, 0.079 SINGLE ROW HEADER, 3-PIN
SULLINS, NRPN031PAEN-RC
16
3
XJP1, XJP2, XJP3
SHUNT, 0.079" CENTER
SAMTEC, 2SN-BK-G
17
4
STAND-OFFS
STAND-OFF, NYLON 0.5"
KEYSTONE, 8833 (SNAP ON)
Hardware
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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 representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
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DEMO MANUAL DC2057A
SCHEMATIC DIAGRAM
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DEMO MANUAL DC2057A
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
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Linear Technology Corporation
LT 0114 • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507 ● www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2014
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