DC2372A - Demo Manual

DEMO MANUAL DC2372A
LTC3121EDE
High Efficiency 15V 1.5A
Synchronous Step-Up Converter
Description
Demonstration circuit 2372A is a 5.5V input, 12V output
at 400mA DC/DC power supply featuring the LTC®3121.
The IC includes internal high and low side 1.5A switches
and features selectable PWM or Burst Mode® operation
for high efficiency at low output current. The board operates from an input voltage as low as 1.8V and continues
to operate down to 500mV once started. The output is
fixed at 12V although other voltages between 2.2V and
15V can be selected by resistor changes.
The IC includes soft-start and input current limit, adjustable switching frequency with the ability to synchronize
to an external clock, and output overvoltage protection
with output disconnect.
Performance Summary
PARAMETER
Included on the board are jumpers for ON/OFF and operating MODE, PWM or BURST. Terminals are included for
connecting VIN and VOUT as well as ON/OFF and SYNC.
The LTC3121 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/DC2372A
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
1.8V to 5.5V
Output Voltage
VIN = 5V, VOUT Load = 400mA
12V ±3%
Output Current
VIN = 5V, VOUT = 12V
400mA
Output Voltage Ripple (PWM Mode)
VIN = 5V, VOUT = 12V, VOUT Load = 400mA
40mVP-P
Output Voltage Ripple (Burst Mode Operation)
VIN = 5V, VOUT = 12V, VOUT Load = 50mA
Switching Frequency
200mVP-P
1MHz ±15%
dc2372af
1
DEMO MANUAL DC2372A
Quick Start Procedure
This Demonstration circuit 2372A can be evaluated using
the setup shown in Figure 1.
1.Connect voltmeters to VIN and VOUT, select upper positions for jumper JP1 (ON) and JP2 (PWM).
2.With input power supply set for 0V, connect the supply
to VIN and GND terminals.
3.Slowly increase the input power supply to 1.8V. Observe
output voltage and verify that it meets the specifications
in the Performance Summary table.
6V, 3A
Adjustable
Power Supply
4.Connect a suitable load resistor or active load to the
output terminals and verify that it meets specifications
in the Performance Summary table.
5.Use a scope to monitor the output voltage ripple in
both PWM mode and Burst Mode operation by moving
the mode jumper JP2 to the appropriate position. See
Figure 4 for correct method for evaluating output ripple.
6.Note: If jumper JP2 is set for Burst Mode operation,
maximum output current is limited to approximately
100mA at 5VIN.
–
–
LOAD
+
+
Figure 1. Proper Measurement Equipment Setup
2
dc2372af
DEMO MANUAL DC2372A
Quick Start Procedure
100
90
Burst Mode
OPERATION
90
80
70
EFFICIENCY (%)
EFFICIENCY (%)
80
100
60
50
40
PWM MODE
30
60
50
30
20
10
10
1
10
100
LOAD CURRENT (mA)
1000
PWM MODE
40
20
0
0.1
Burst Mode
OPERATION
70
0
0.1
1
dc2372a F02
Figure 2. Efficiency VIN = 2V
10
100
LOAD CURRENT (mA)
1000
dc2372a F03
Figure 3. Efficiency VIN = 5V
Figure 4. Measuring Output Voltage Ripple
dc2372af
3
DEMO MANUAL DC2372A
Parts List
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
1
1
C1
CAP 10μF X5R 10V 10%1206
TDK, C3216X5R1A106K
2
1
C2
CAP 0.10μF X7R 50V 10% 0603
TDK, CGA3E2X7R1H104K080AA
3
1
C3
CAP 4.7μF X5R 25V 10% 0805
TDK,C2012X5R1E475K085AC
4
0
C4
CAP 0402 OPT
OPT
5
1
C5
CAP 22μF 25V X5R 10% 1210
MURATA, GRM32ER61E226KE15L
6
1
C7
CAP 1μF X7R 25V 10% 0603
TDK, CGA3E1X7R1E105K080AC
7
1
C8
CAP 1nF 50V X7R 10% 0402
AVX, 04025C102KAT2A
8
1
C9
CAP 10pF C0G 25V 5% 0402
AVX, 04023A100JAT2A
9
6
E1-E6
TEST POINT, TURRET, 0.094 MTG. HOLE
MILL-MAX, 2501-2-00-80-00-00-07-0
10
2
JP2, JP1
CONN, HEADER, 1 × 3, 2mm
SAMTEC, TMM-103-02-L-S
11
2
XJP1, XJP2
SHUNT, 2mm
SAMTEC, 2SN-BK-G
12
1
L1
IND, PWR 6.8μH, 20%, XAL40xx Series
COILCRAFT, XAL4030-682ME
13
1
R1
RES, 1MΩ 1/10W 1% 0402
PANASONIC, ERJ2RKF1004X
14
1
R2
RES, 57.6kΩ 1/10W 1% 0402
PANASONIC, ERJ2RKF5762X
15
0
R3
RES,0402 OPT
OPT
16
1
R4
RES 1.02MΩ 1/10W 1% 0402
VISHAY, CRCW04021M02FKED
17
1
R5
RES, 113kΩ 1/10W 1% 0402
PANASONIC, ERJ2RKF1133X
18
1
R6
RES, 82.5kΩ 1/10W 1% 0402
PANASONIC, ERJ2RKF8252X
19
1
U1
IC, LTC3121EDE
LINEAR TECH, LTC3121EDE
STAND OFF
20
4
STAND-OFF, NYLON 0.500"
KEYSTONE, 8832 (SNAP ON)
21
1
FAB, PRINTED CIRCUIT BOARD
LINEAR TECH, DEMO CIRCUIT 2372A
22
2
STENCILS, TOP & BOTTOM
LINEAR TECH, DEMO CIRCUIT 2372A
4
dc2372af
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
JP2
1
2
3
1
2
3
VCC
C1
10uF
10V
1206
VIN
R1
1M
1%
5
2. INSTALL SHUNTS AS SHOWN.
1. ALL RESISTORS ARE 0402 AND CAPACITORS ARE 0603.
NOTE: UNLESS OTHERWISE SPECIFIED
BURST
PWM
MODE
E4
JP1
RUN
E3
E2
SYNC
ON
OFF
RUN
GND
E1
VIN
1.8V - 5.5V
4
4
R2
57.6k
1%
2
10
6
4
9
3
PGND
GND
RT
SW
VCC
VC
FB
VOUT
CAP
1
C3
4.7uF
0805
5 VCC
7
8
11
12
R6
82.5k
1%
C8
1nF
0402
C2
0.1uF
50V
3
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
CUSTOMER NOTICE
3
1%
R3
OPT
C4
OPT
0402
2
2
SCALE = NONE
Goran P.
HZ
APPROVALS
C9
10pF
0402
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO PCB DES.
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APP ENG.
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
PWM/SYNC
SHDN/
VIN
XAL4030
U1
LTC3121EDE
6.8uH
L1
GND
13
5
1
C5
22uF
25V
1210
E6
GND
12V
400mA
VOUT
DATE
12-5-14
A
B
C
D
DATE:
N/A
SIZE
LTC3121EDE
DEMO CIRCUIT 2372A
05 - 16 - 12
IC NO.
1
SHEET
1
OF
1
1
REV.
15V, 1.5A SYNCHRONOUS BOOST DC / DC CONVERTER
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900 www.linear.com
Fax: (408)434-0507
LTC Confidential-For Customer Use Only
C7
1uF
25V
E5
Goran P.
PROTOTYPE
VOUT
APPROVED
DESCRIPTION
TECHNOLOGY
REV
TITLE: SCHEMATIC
R5
113K
1%
R4
1.02M
1%
__
ECO
1
REVISION HISTORY
DEMO MANUAL DC2372A
Schematic Diagram
dc2372af
5
DEMO MANUAL DC2372A
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
6
dc2372af
Linear Technology Corporation
LT 0715 REV A • 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