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dc2105af
DEMO MANUAL DC2105A
Description
LTC3630AEMSE/LTC3630EMSE
High Efficiency High Voltage 500mA
Synchronous Step-Down Converter
Demonstration circuit 2105A is a 500mA output DC/DC
power supply. There are two versions: DC2105A-A is a
board featuring
LTC
®
3630A
, with 4V to 76V input range;
DC2105A-B is a board featuring LTC3630, with 4V to 65V
input range. The LTC3630A/LTC3630 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/LTC3630 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. Ad-
ditional PC pads are included for programming current
limit to optimize efficiency and for reducing output voltage
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.
performance summary
ripple and reducing component size. A terminal (FBO)
is available to allow multiple boards to be paralleled for
increasing output current.
Output voltage between 800mV and V
IN
can be pro-
grammed using optional resistors, although higher voltage
output capacitors will be required.
The LTC3630A/LTC3630 data sheet gives a complete de-
scription 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/DC2105A
Specifications are at T
A
= 25°C
PARAMETER
CONDITION
VALUE
Input Voltage Range for DC2105A-A
LTC3630A
4V to 76V
Input Voltage Range for DC2105A-B
LTC3630
4V to 65V
1.8V Output
V
IN
= 20V, V
OUT
Load = 100mA
1.8V ±2%
3.3V Output
V
IN
= 20V, V
OUT
Load = 100mA
3.3 V ±2%
5V Output
V
IN
= 20V, V
OUT
Load = 100mA
5V ±2%
Maximum Output Current
V
IN
= 20V, V
OUT
= 5V
500mA
Typical Output Voltage Ripple
V
IN
= 20V, V
OUT
= 5V
75mV
P-P
