DC2275A - Demo Manual

DEMO MANUAL DC2275A
LT8331
Boost/SEPIC/Inverting
Regulator
DESCRIPTION
Demonstration circuit DC2275A features the LT®8331 in
boost configuration. The demo circuit demonstrates small
size and low component count. The boost is designed to
convert a 10V to 48V source to 120V at 25mA to 80mA.
DC2275A includes an optional circuit on the back of the
board for a charge pump that can be used to double the
output voltage.
The default mode for this application is pulse-skip mode,
but removal of R13 allows for other modes to be used
for different applications. A jumper from sync to ground
will put the converter in Burst Mode® operation, or an
external clock can be used to synchronize the converter
to an external frequency.
PERFORMANCE SUMMARY
SYMBOL
PARAMETER
VIN
Input Supply Range
VOUT
Output Voltage Range
The LT8331 can operate with inputs as high as 100V but
in this demo circuit, the input is limited by the voltage
rating of the input capacitor.
The LT8331 includes many other features such as synchronization to external clock, user configurable undervoltage
lockout, soft-start, frequency foldback, and it is easily
configured as boost, SEPIC or inverting converter.
The data sheet gives a complete description of the device,
operation and application information. The data sheet must
be read in conjunction with this demo manual for DC2275A.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2275A
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
CONDITIONS
MIN
TYP
10
VIN = 12V, ILOAD = 30mA
116.4
MAX
48
120
123.6
UNITS
V
V
RIPPLE
VIN = 12V, ILOAD = 30mA
200
mV
EFFICIENCY
VIN = 24V, ILOAD = 55mA
90
%
EFFICIENCY
VIN = 12V, ILOAD = 30mA
SWITCHING FREQUENCY
79
%
200
kHz
dc2275af
1
DEMO MANUAL DC2275A
QUICK START PROCEDURE
Demonstration circuit DC2275A is easy to set up to evaluate the performance of the LT8331. 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 3 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 48V.
3. 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.
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.
Figure 1. DC2275A Proper Equipment Setup
dc2275af
2
DEMO MANUAL DC2275A
QUICK START PROCEDURE
GND
VIN
Figure 2. Measuring Input or Output Ripple
100
90
VIN = 24V
EFFICIENCY (%)
80
VIN = 12V
70
60
50
40
30
20
10
0
5 10 15 20 25 30 35 40 45 50 55 60
LOAD CURRENT (mA)
dc2275 F03
Figure 3. Efficiency vs Load
dc2275af
3
DEMO MANUAL DC2275A
PARTS LIST
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
Required Circuit Components
1
1
C3
CAP., X5R 10µF 50V 10% 1206
MURATA, GRM31CR61H106KA12L
2
2
C4, C5
CAP., X7R 1µF 250V 10% 2220
MURATA, GRM55DR72E105KW01L
3
1
C6
CAP., X7R 0.22µF 25V 10% 0603
MURATA, GRM188R71E224KA88D
4
1
C7
CAP., X5R 1µF 25V 20% 0603
AVX, 06033D105MAT2A
5
1
C8
CAP., C0G, 4.7pF, 250V, ±0.25pF, 0805
MURATA, GQM2195C2E4R7CB12J
6
1
D3
DIODE, SCHOTTKY, SOD123
DIODES INC., BAV21W-7-F
7
1
L1
INDUCTOR, 330µH ± 20%
SUMIDA, CDRH8D43RT125NP-331MC
8
1
R3
RES., CHIP 1M 0.1W 5% 0603
VISHAY, CRCW06031M00JNEA
9
1
R5
RES., CHIP 1M 0.125W 1% 0805
VISHAY, CRCW08051M00FKEA
10
1
R7
RES., CHIP 13.3k 0.1W 1% 0603
VISHAY, CRCW060313K3FKEA
11
1
R8
RES., CHIP 154k 0.1W 1% 0603
VISHAY, CRCW0603154KFKEA
12
1
R12
RES., CHIP 215k 0.1W 1% 0603
VISHAY, CRCW0603215KFKEA
13
1
R13
RES., CHIP 0Ω 0.1W 1% 0603
VISHAY, CRCW06030000Z0EA
14
1
U1
I.C., CONVERTER CONTROLLER
LINEAR TECH. CORP. LT8331EMSE
15
1
FAB, PRINTED CIRCUIT BOARD
DEMO CIRCUIT 2275A
Additional Demo Board Circuit Components
1
0
C1 (Opt)
CAP., 1206
2
0
C2 (OPT)
CAP., 2220
4
0
D1, D2 (OPT)
DIODE, SOD123
5
0
R2 (OPT)
RES., 1206
6
0
R6 (OPT)
RES., 0603
Hardware: For Demo Board Only
1
7
E1, E2, E3, E4, E5, E6, E7
TURRET, TESTPOINT
MILL-MAX, 2501-2-00-80-00-00-07-0
2
4
MH1-MH4
STANDOFF, NYLON 0.25"
KEYSTONE, 8831 (SNAP-ON)
dc2275af
4
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.
A
B
C
D
GND
SYNC
EN/UVLO
GND
VIN
10V ‐ 48V
5
E4
E3
E5
E2
E1
5
R12
215K
1%
R6
(Opt)
R13
0
INTVCC
R3
1M
10
11
R8
154k
1%
C6
0.22µF
1
12
C3
10µF
50V
1206
BIAS
VIN
4
RT
SS
SYNC
5
9
14
16
70mA
80mA
48V
30mA
12V
55mA
25mA
10V
36V
IOUT
C4
1µF
250V
2220
VIN
*
BAV21W‐7‐F
D3
R2
OPT
1206
OPT
OPT
1206
D2
OPT
D1
C1
24V
3
R7
13.3K
1%
2
C2
OPT
2220
2
C5
1µF
250V
2220
OPTIONAL CIRCUIT
17
C7
1µF
INTVCC
CDRH8D43RT125NP‐331MC
L1
330µH
Sumida
3
GND
6
NC 8
NC
INTVCC
FBX
SW
U1
LT8331EMSE
SW
7
3
UVLO
4
R5
0805
1M 0805
4.7pF
C8
E7
E6
GND
1
120V
VOUT
1
*
A
B
C
D
DEMO MANUAL DC2275A
SCHEMATIC DIAGRAM
dc2275af
5
DEMO MANUAL DC2275A
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
dc2275af
6
Linear Technology Corporation
LT 1015 • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507 ● www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2015
Similar pages