DC1636A - Demo Manual

DEMO MANUAL DC1636A
LT3574
Isolated Monolithic
Flyback Converter
DESCRIPTION
Demonstration circuit 1636A is an isolated flyback converter featuring the LT®3574. This demo circuit is designed
for a 5.0V output from a 10V to 30V input. The maximum
output current is 0.5A when the input voltage is higher
than 20V. No third winding or opto-isolator is required
for regulation. The part senses the isolated output voltage
directly from the primary-side flyback waveform.
The LT3574 operates with input supply voltages from 3V
to 40V, and can deliver an output power up to 3W with
no external power switch. The LT3574 utilizes boundary
mode operation to provide a small magnetic solution
PERFORMANCE SUMMARY
PARAMETER
with improved load regulation. The LT3574 can be used
in industrial, automotive and medical applications where
an isolated output is required.
The LT3574 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 1636A.
Design files for this circuit board are available at
http://www.linear.com/demo
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.
Specifications are at TA = 25°C
CONDITION
MIN
Output Voltage VOUT
VIN = 10V ~ 30V
4.75
Maximum Output Current IOUT
VIN = 10V ~ 20V
VIN = 20V ~ 30V
0.35
0.50
Switching Frequency
VIN = 12V, IOUT = 0.35A
VIN = 24V, IOUT = 0.5A
200
270
kHz
kHz
Voltage Ripple VOUT
VIN = 24V, IOUT = 0.5A
50
mV
Efficiency
VIN = 24V, IOUT = 0.5A
84
%
Input Voltage
TYP
MAX
30
V
5.0
5.25
V
10
UNITS
A
A
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DEMO MANUAL DC1636A
QUICK START PROCEDURE
Demo circuit 1636A is easy to set up to evaluate the
performance of the LT3574. 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. 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 30V.
3.Check for the proper output voltages.
Note: If there is no output, temporarily disconnect the
load to make sure that the load current is not set too high.
4.Once the proper output voltage is established, adjust
the load current within the operating range and observe
the output voltage regulation, ripple voltage, efficiency
and other parameters.
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DEMO MANUAL DC1636A
QUICK START PROCEDURE
Figure 1. Proper Measurement Equipment Setup
VIN OR VOUT
GND
Figure 2. Measuring Input or Output Ripple
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DEMO MANUAL DC1636A
PARTS LIST
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
Required Circuit Components
1
1
C2
CAP, 1210 4.7µF 10% 50V X7R
AVX 12105C475KAT2A
2
1
C4
CAP, 1210 47µF 10% 10V X7R
MURATA GRM32ER71A476K
3
1
C7
CAP, 0402 0.1µF 10% 25V X5R
TDK C1005X5R1E104K
4
1
C8
CAP, 0402 100pF 5% 50V NPO
AVX 04025A101JAT2A
5
2
C12, C9
CAP, 0805 1µF 10% 50V X7R
MURATA GRM21BR71H105K
6
1
C10
CAP, 0805 0.22µF 10% 50V X7R
TAIYO YUDEN UMK212BJ224KG-T
7
1
C11
CAP, 0402 4700pF 10% 50V X7R
TDK C1005X7R1H472K
8
1
C13
CAP, 0402 10pF 5% 50V NPO
MURATA1555C1H100JZ01D
9
1
D1
DIODE, SCHOTTKY, BARRIER RECTIFIER 2A
DIODES INC B240A-13-F
10
1
D2
DIODE, RECTIFIER, BARRIER, SCHOTTKY 1.0A
DIODES INC. DFLS1100
11
1
D3
DIODE, SCHOTTKY SOD323
CENTRAL SEMI CMDSH-3
12
1
R3
RES, 0402 357K OHMS 1% 1/16W
VISHAY CRCW0402357KFKED
13
1
R6
RES, 0402 93.1k 1% 1/16W
VISHAY CRCW040293K1FKED
14
1
R7
RES, 0402 84.5k 1% 1/16W
VISHAY CRCW040284K5FKED
15
1
R8
RES, 0805 4.02k 1% 1/8W
VISHAY CRCW08054K02FKEA
16
1
R9
RES, 0402 20k 1% 1/16W
VISHAY CRCW040220K0FKED
17
1
R10
RES, 0402 10k 1% 1/16W
VISHAY CRCW040210K0FKED
18
1
R11
RES, 0402 6.04k 1% 1/16W
NIC NRC04F6041TRF
19
1
R15
RES, 0402 12.4k 1% 1/16W
VISHAY CRCW040212K4FKED
20
1
T1
TRANSFORMER
WURTH 750370041
21
1
U1
IC, MONOLITHIC FLYBACK CONVERTER
LINEAR TECH LT3574EMS
Additional Demo Board Circuit Components
1
1
C1
CAP, 22µF 20% 50V ELECT.
SANYO 50CE22BS
2
0
C5
CAP, 22µF 20% 50V ELECT. OPTION
SANYO 50CE22BS OPTION
3
0
C14
CAP, 1206 0.033µF 10% 50V X7R OPTION
AVX 12065C333KAT2A OPTION
4
0
C19
CAP, 1210 4.7µF 10% 50V X7R OPTION
MURATA GRM32ER71H475K OPTION
5
0
C20
CAP, 0603 0.01µF 10% 50V X7R OPTION
NIC NMC0603X7R104K50TRPF OPTION
6
0
FB1
FERRITE BEAD OPTION
TAIYO YUDEN FB MJ3216HS800 OPTION
7
0
L1
IND, 10uH OPTION
SUMIDA CDRH4D22/HP OPTION
8
0
R2
RES, 0603 OPTION
OPTION
9
1
R4
RES, 0805 1.4k 1% 1/8W
VISHAY CRCW08051K40FKEA
TURRET
MILL-MAX 2501-2-00-80-00-00-07-0
Hardware-For Demo Board Only
1
5
E1, E2, E3, E5, E6
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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.
E1
E3
22
50V
+C1
R10
10K
1%
C7
0.1
SANYO
50CE22BS
VIN
C8
100pF
C2
4.7
50V
1210
C12
1
50V
0805
12
10
11
C11
4700pF
VC
SS
RILIM
TC
RREF
RFB
SW
R11
6.04K
1%
R7
84.5K
1%
C9
1
50V
0805
C13
10pF
D2
DFLS1100
C10
0.22
50V
0805
2
R8
4.02K
1%
0805
T1
CONTRACT NO.
4
3
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
C20
0.01
0603
50V
DATE:
A
SIZE
BEAD
C4
47
1210
10V
0.033uF
C19
4.7
50V
1210
1206
10uH
E5
APPROVED
Zhongming Y.
VOUT-
22
50V
SANYO
50CE22BS
E6
+C5
VIN
VOUT-
[email protected], VIN > 20V
VOUT+
[email protected], VIN < 20V
VOUT+
06-05-13
DATE
1
IC NO.
LT3574EMS
2
1
SHEET
DEMO CIRCUIT 1636A
ISOLATED MONOLITHIC FLYBACK
CONVERTER
OF
1-1
REV
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900
Fax: (408)434-0507
LTC Confidential-For Customer Use Only
SUMIDA
CDRH4D22/HP
L1
TECHNOLOGY
C14
TAIYO YUDEN
FB MJ3216HS800
FB1
R4
1.4K
1%
0805
CHANGED: C11,R15,R4
DESCRIPTION
REVISION HISTORY
OPTIONAL CIRCUIT
1
D1 B240A
2
VIN
1-1
REV
2
TITLE: SCHEMATIC
8
7
5
6
ECO
750370041
3
4
2
1
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
APPROVALS
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO PCB DES.
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
ENG.
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
CUSTOMER NOTICE
14
13
4
R2
0603
OPT
1
D3 CMDSH-3
3
3
1
0
2
,
5
0
e
n
u
J
,
y
a
d
s
e
n
d
e
W
5
U1
LT3574EMS
SHDN/UVLO
2. ALL CAPACITOR VALUES ARE IN MICROFARADS,
AND CASE SIZES ARE 0402.
1. ALL RESISTOR CASE SIZES ARE 0402.
7
15
R15
12.4K
1%
R3
357K
1%
R6
93.1K
1%
NOTES: UNLESS OTHERWISE SPECIFIED,
R9
20K
1%
SHDN
GND
E2
VIN
10V - 30V
4
I
M
A
B
C
D
5
VIN
6
BIAS
TEST
GND
GND
GND
GND
GND
2
1
3
8
9
16
1
2
5
A
B
C
D
DEMO MANUAL DC1636A
SCHEMATIC DIAGRAM
1
1
.
Z
R
E
G
I
T
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DEMO MANUAL DC1636A
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 0913 • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507 ● www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2013