DC1853A - Demo Manual

DEMO MANUAL DC1853A
LT3959
Wide Input Voltage Range
Boost/SEPIC/Inverting Converter
DESCRIPTION
The LT®3959 is a current mode DC/DC converter with an
integrated 6A, 40V switch. It can operate over an input
range of 1.6V to 40V, suitable for applications from singlecell lithium-ion battery portable electronics up to high
voltage automotive and industrial power supplies. It also
exhibits low shutdown quiescent current of <1μA, making
it an ideal fit for battery-operated systems. Thanks to a
novel FBX pin architecture, the LT3959 can be connected
directly to a divider from either positive or negative output
to ground. It also packs many popular features such as
soft-start, input undervoltage lockout, adjustable frequency
and synchronization.
Demonstration circuit 1853A features LT3959 in a 300kHz
boost converter, designed for 12V output from 2V to 10V
input (VIN). The performance is summarized in the table
below.
PERFORMANCE SUMMARY
PARAMETER
The demo circuit has small circuit footprint, and can be
modified to generate different output voltages. The performance can be optimized for different input voltage ranges
as well. It is a high performance and cost-effective solution
for battery-operated systems, telecom, and automotive
applications.
The LT3959 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. Proper board layout is essential for both proper
operation and maximum thermal performance. See the
Applications Information section of the data sheet for
more information.
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
CONDITIONS
Input Voltage Range
MIN
2
Input Turn-On Voltage (Rising)
Input Undervoltage Lockout (Falling)
Switching Frequency
IOUT = 0.5A
Output Voltage
Maximum Output Current
TYP
MAX
10
V
2.5
V
2
V
300
11.64
UNITS
12
kHz
12.36
V
VIN ≥ 2V
0.5
A
VIN ≥ 5V
1
A
VIN ≥ 9V
2
A
Output Voltage Ripple
VIN = 5V, IOUT = 1A
75
Efficiency
VIN = 10V, IOUT = 2A
94
100
mV
%
dc1853af
1
DEMO MANUAL DC1853A
QUICK START PROCEDURE
Demo circuit 1853A is easy to set up to evaluate the performance of LT3959. Refer to Figure 1 for proper measurement equipment setup and follow the procedure below.
1. With power off, connect the input power supply, load
and meters as shown in Figure 1. Preset the load to 0A,
and VIN supply to be 0V. Place jumpers in the following
positions.
EN (JP1)
SYNC (JP2)
ON
OFF
2. Turn on VIN and increase to 2.5V. Check for proper
output voltages. The output should be regulated at
12V (±3%). The switching frequency should be about
300kHz.
NOTE. If there is no output, or the output is out of spec,
temporarily disconnect the load to make sure that the
load is not set too high.
NOTE. Make sure that the input voltage does not exceed
specification. If higher operating voltage is required,
power components with higher voltage ratings should
be used. The maximum voltage is 40V for the integrated
switch of LT3959.
NOTE. The demo circuit configures the shutdown voltage at 2V, which means that the input voltage can be
dropped to as low as 2V, once it starts up. The startup
voltage is set at 2.5V, and can be adjusted by changing
R1 and R2 values.
NOTE. The output current capability depends on the
input voltage. The output current is up to 0.5A for VIN
higher than 2V, 1A for VIN higher than 5V, and 2A for
VIN higher than 9V.
3. Once the proper output voltage is established, adjust
the input voltage and load within the operating range
and observe the output voltage regulation, ripple voltage, efficiency and other parameters. Typical efficiency
curve is shown in Figure 3.
NOTE. When measuring the input or output voltage
ripples, 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 and GND, or VOUT and GND terminals.
See Figure 2 for proper scope probe technique.
Figure 1. Proper Measurement Equipment Setup
dc1853af
2
DEMO MANUAL DC1853A
QUICK START PROCEDURE
INPUT OR OUTPUT CAPACITOR
Figure 2. Proper Scope Probe Placement for Measuring Input or Output Ripple
Efficiency vs Load Current
100
VIN = 10V
EFFICIENCY (%)
95
90
VIN = 5V
85
80
75
70
0
400
800
1200
1600
LOAD CURRENT (mA)
2000
dn1853a F03
Figure 3. Efficiency with Different Input Voltages
dc1853af
3
DEMO MANUAL DC1853A
PARTS LIST
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
Required Circuit Components
1
5
C1, C9, C10, C11, C12
CAP., X7R, 22μF 16V, 10%, 1210
AVX, 1210YC226KAT2A
2
1
C4
CAP., SVPC 68μF 16V, 20%, OSCON-C6
SANYO, 16SVPC68MV
3
1
C5
CAP., NPO, 120pF 25V, 10%, 0603
AVX, 06033A121KAT
4
1
C6
CAP., X7R 18nF 25V, 20%, 0603
AVX 06033C183MAT2A
5
1
C7
CAP., X5R, 0.33μF 16V, 10%, 0603
AVX, 0603YD334KAT
6
1
C8
CAP., X5R, 4.7μF 10V, 10%, 0603
TAIYO YUDEN, LMK107BJ475KA-T
7
1
D1
SCHOTTKY DIODE, 2A/30V POWERDI-123
DIODES/ZETEX DFLS230LH-7
8
1
L1
IND., 3.3μH
COOPER BUSSMANN, DR74-3R3-R
9
1
R1
RES., CHIP 332k 1/10W, 1%, 0603
VISHAY, CRCW0603332KFKEA
10
1
R2
RES., 200k 1%, 1/10W, 0603
VISHAY, CRCW0603200KFKEA
11
1
R3
RES., 102k 1%, 1/10W, 0603
VISHAY, CRCW0603102KFKEA
12
1
R4
RES., 15.8k 1%, 1/10W, 0603
VISHAY, CRCW060315K8FKEA
13
1
R5
RES., CHIP 10.5k 1/10W, 1%, 0603
VISHAY, CRCW060310K5FKEA
14
1
R6
RES., 27.4k 1%, 1/10W, 0603
VISHAY, CRCW060327K4FKEA
15
1
R7
RES., 100k 1%, 1/10W, 0603
VISHAY, CRCW0603100KFKEA
16
1
U1
I.C., DC/DC CONVERTER
QFN (36) (UHE28MA) (5MMX6MM) (1836-REVC)
LINEAR TECH., LT3959EUHE
AVX, 1210YC226KAT2A
Additional Demo Board Circuit Components
1
0
C2
CAP., X7R, 22μF 16V, 10%, 1210
2
0
C13, C14
CAP., 0603
Hardware: For Demo Board Only
1
10
E1-E10
TESTPOINT, TURRET, 0.094"
MILL-MAX, 2501-2-00-80-00-00-07-0
2
2
3
2
JP1, JP2
HEADER, 3 PIN 1 ROW, 0.079"
SAMTEC, TMM-103-02-L-S
XJP1, XJP2
SHUNT, 0.079" CENTER
SAMTEC, 2SN-BK-G
4
4
M1-M4
STANDOFF, NYLON 0.25"
KEYSTONE, 8831 (SNAP-ON)
5
6
1
FAB, 1853A_REV2
DEMO CIRCUIT 1853A
1
STENCIL - TOP
STENCIL 1853A
dc1853af
4
DEMO MANUAL DC1853A
SCHEMATIC DIAGRAM
dc1853af
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.
5
DEMO MANUAL DC1853A
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
dc1853af
6
Linear Technology Corporation
LT 0912 • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507 ● www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2012
Similar pages