Linear Technology DC2056A Quick setup guide

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DEMO MANUAL DC2056A
DESCRIPTION
LTC3637EMSE
High Efficiency 76V, 1A
Step-Down Converter
Demonstration circuit 2056A is a 76V input, 1A output
DC/DC power supply featuring the LT C
®
3637. The IC oper-
atesin
ahighefficiencyBurstMode
®
operationandincludes
an internal high side power MOSFET. The board will accept
an input voltage between 4V and 76V, and provide jumper
selected output voltages of 1.8V, 3.3V, 5V and 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. 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.
PERFORMANCE SUMMARY
Output voltage between 800mV and VIN can be pro-
grammed using optional resistors. (Higher voltage rating
output capacitors may be required.)
TheLTC3637datasheet gives acompletedescription 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
Specifications are at TA= 25°C
PARAMETER CONDITION VALUE
Input Voltage Range 4V to 76V
1.8V Output Voltage VIN = 12V, IOUT = 0A to 1A 1.8V ±2%
3.3V Output Voltage VIN = 12V, IOUT = 0A to 1A 3.3V ±2%
5V Output Voltage VIN = 12V, IOUT = 0A to 1A 5V ±2%
Maximum Output Current, IOUT VIN = 4V to 76V, VOUT = 1.8V, 3.3V or 5V 1A
Typical Efficiency VIN = 12V, VOUT = 5V, IOUT = 1A 85.5%
Typical Output Ripple VIN = 76V, VOUT = 5V, IOUT = 1A (20MHz BW) 109mVP-P
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DEMO MANUAL DC2056A
QUICK START PROCEDURE
Demonstration circuit 2056A is easy to set up to evaluate
the performance of the LTC3637. Refer to Figure 1 for
the proper measurement equipment setup and follow the
procedure below:
1. With power off, connect the input power supply (set
for 0V) to VIN and GND (input return).
2. Select 5V output using jumper JP1 (B position) and
JP2 (A position). Select ON position for JP3.
3. Connect the 5V output load between VOUT and GND
(Initial load: no load).
4. Connect the DVMs to the input and outputs.
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%.)
6. Once the proper output voltages are established, ad-
just the loads within the operating range and observe
the output voltage regulation, ripple voltage and other
parameters.
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 out-put voltage and other
parameters.
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.
Additional Notes
1. CAUTION: Be careful when testing with high voltage.
High voltage can result in an electric shock if care
is not taken.
2. For 5V output, VIN input voltage should be at least 5V
or higher.
Downloaded from Arrow.com.Downloaded from Arrow.com.

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DEMO MANUAL DC2056A
QUICK START PROCEDURE
+ –
VOUT GND
COUT
Figure 1. Proper Measurement Equipment Setup
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DEMO MANUAL DC2056A
QUICK START PROCEDURE
LTC3637 3.3VOUT Efficiency vs Load Current
LTC3637 1.8VOUT Efficiency vs Load Current
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DEMO MANUAL DC2056A
QUICK START PROCEDURE
LTC3637 5VOUT Efficiency vs Load Current
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DEMO MANUAL DC2056A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 1 C1 CAP, 47µF 20% 100V ALUM NIPPON CHEMI-CON EMVY101ARA470MKE0S
2 1 C2 CAP, 2220 4.7µF 20% 100V X7R TDK C5750X7R2A475M
3 1 C3 CAP, 0603 47pF 5% 50V C0G AVX 06035A470JAT2
4 1 C4 CAP, 0603 47nF 10% 25V X7R AVX 06033C473KAT
5 2 C6, C7 CAP, 1210 100µF 20% 10V X5R MURATA GRM32ER61A107ME20L
6 1 C9 CAP, 0603 0.1µF 10% 25V X7R AVX 06033C104KAT2A
7 1 D1 DIODE, SUPER BARRIER RECTIFIER DIODES INC. SBR3U100LP
8 1 L1 IND, 10µH 30% 4.45A SMD SUMIDA CDRH105RNP-100NC
9 1 R1 RES, 0603 1M 5% 1/10W NIC NRC06J105TRF
10 1 R4 RES, 0603 255k 1% 1/10W VISHAY CRCW0603255KFKEA
11 2 R5, R6 RES, 0603 0Ω JUMPER VISHAY CRCW06030000Z0EA
12 1 U1 IC, HIGH EFFICIENCY STEP-DOWN CONVERTER LINEAR TECH. LTC3637EMSE
Additional Demo Board Circuit Components
1 0 C8, C10, C11 CAP, 1210 OPTION OPTION
2 0 R2, R3, R7 RES, 0603 OPTION OPTION
Hardware
1 5 E1, E2, E3, E4, E5 TURRET MILL MAX 2501-2-00-80-00-00-07-0
2 3 JP1, JP2, JP3 HEADER, 3-PIN, 2mm SAMTEC TMM-103-02-L-S
3 3 JP1, JP2, JP3 SHUNT, 2mm SAMTEC 2SN-BK-G
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DEMO MANUAL DC2056A
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 C C B B A A
BB
B
B A
A
AA
ON
OFF
2.
VIN
4V - 76V
GND
FBO
VOUT
1.8V/3.3V/5V
1A
GND
BA
1. ALL RESISTORS AND CAPACITORS ARE 0603.
NOTE: UNLESS OTHERWISE SPECIFIED
JP1 JP2VOUT
BA
1.8V
3.3V
5.0V
EXT. R
2
3 1
1 1
3 3
2
2
3. FOR 5VOUTPUT, VIN RANGE IS
6V - 76V.
VOUTVIN
VIN
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

TECHNOLOGY
    
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        
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11/04/13 12:46:41
11
HIGH EFFICIENCY, 76V, 1A STEP-DOWN


N/A
LTC3637EMSE
DEMO CIRCUIT 2056A
CONVERTER
 
 
 




TECHNOLOGY
    
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        
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

1
11/04/13 12:46:41
11
HIGH EFFICIENCY, 76V, 1A STEP-DOWN


N/A
LTC3637EMSE
DEMO CIRCUIT 2056A
CONVERTER
 
 
 




TECHNOLOGY
    

        




1
11/04/13 12:46:41
11
HIGH EFFICIENCY, 76V, 1A STEP-DOWN


N/A
LTC3637EMSE
DEMO CIRCUIT 2056A
CONVERTER
REVISION HISTORY
DESCRIPTION DATE APPROVEDECO REV
CHARLIE Z.
PROD
111/04/13
REVISION HISTORY
DESCRIPTION DATE APPROVEDECO REV
CHARLIE Z.
PROD
111/04/13
REVISION HISTORY
DESCRIPTION DATE APPROVEDECO REV
CHARLIE Z.
PROD
111/04/13
C6
100uF
10V
1210
C6
100uF
10V
1210
C8
OPT
1210
C8
OPT
1210
R7 OPT R7 OPT
+
C1 47uF 100V
+
C1 47uF 100V C9
0.1uF
C9
0.1uF
R3
OPT
R3
OPT
R2 OPT R2 OPT JP3JP3
L1 10uH
CDRH105R
L1 10uH
CDRH105R
C10
OPT
1210
C10
OPT
1210
E3E3
C11
OPT
1210
C11
OPT
1210
U1
LTC3637EMSE
U1
LTC3637EMSE
SW 1
VIN
3
OVLO
12
VPRG1 7 VPRG2 6
GND
8
VFB 9
SS 10
ISET
11
FBO
5
RUN
14
GND
16
GND
17
E4E4
R1 1M R1 1M
JP2JP2
E5E5
R6
0
R6
0
R5
0
R5
0
R4
255K
1% R4
255K
1%
C3
47pF
C3
47pF
D1
SBR3U100LP
D1
SBR3U100LP
JP1JP1
E2E2
C2
4.7uF
100V
2220
C2
4.7uF
100V
2220 C7
100uF
10V
1210
C7
100uF
10V
1210
E1E1
C4
47nF
C4
47nF
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8
dc2056af
DEMO MANUAL DC2056A
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ●FAX: [phone] ●www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2014
LT 0214 • 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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