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dc1877af
DEMO MANUAL DC1877A
Description
LTC3630AEDHC
High Efficiency High Voltage 500mA
Synchronous Step-Down Converter
Demonstration circuit 1877A is a 500mA output DC/DC
power supply featuring
LTC
®
3630A
(DFN package), with
4V to 76V input range. The LTC3630A operates in a high
efficiency Burst Mode
®
operation and includes internal
high and low side switches. The board provides jumper
selected output voltages of 1.8V, 3.3V, 5V and an option
for additional voltages. LTC3630A has 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.
Additional pc pads are included for programming current
limit to optimize efficiency and for reducing output voltage
ripple and reducing component size. A terminal (FBO)
L
, LT, LTC, LTM, Linear Technology, Burst Mode and the Linear logo are registered trademarks
of Linear Technology Corporation. All other trademarks are the property of their respective
owners.
performance summary
is available to allow multiple boards to be paralleled for
increasing output current.
Output voltage between 800mV and V
IN
can be programmed
using optional resistors. (Higher voltage output capacitors
may be required.)
The LTC3630A data sheet gives a complete description of
the operation and application information. The data sheet
must be read in conjunction with this demo manual.
Design files for this circuit board are available at
http://www.linear.com/demo/DC1877A
Table 1. Specifications are at T
A
= 25°C
PARAMETER
CONDITION
VALUE
Input Voltage Range
(1.8V, 3.3V Outputs)
4V to 76V
1.8V Output
V
IN
= 76V, I
OUT
= 500mA
1.8V ±2%
3.3V Output
V
IN
= 76V, I
OUT
= 500mA
3.3V ±2%
5V Output
V
IN
= 76V, I
OUT
= 500mA
5V ±2%
Maximum Output Current
V
IN
= 76V, V
OUT
= 5V
500mA
Typical Output Voltage Ripple
V
IN
= 76V, V
OUT
= 5V
84mV
P-P
Typical Efficiency
(See Figure 3)
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