IRDC3847-P1V2
Confidential
This evaluation board is a preliminary version meant for the engineering evaluation of the IR3847. Based on the results of the
continuing evaluation, this board can evolve and change without notice
2/13/2012
1
USER GUIDE FOR IR3847 EVALUATION BOARD
DESCRIPTION
The
IR3847
is
a
synchronous
buck
converter,
providing
a
compact,
high
performance and flexible solution in a small
5mmx6mm QFN package.
Key features offered by the IR3847 include
internal Digital Soft Start, precision 0.6V
reference voltage, Power Good, thermal
protection,
programmable
switching
frequency, Enable input, input under-voltage
lockout for proper start-up, enhanced line/
load regulation with feed forward, external
frequency
synchronization
with
smooth
clocking,
internal
LDO,
true
differential
remote sensing and pre-bias start-up.
A thermally compensated output over-current
protection function is implemented by sensing
the voltage developed across the on-resistance
of
the
synchronous
rectifier
MOSFET
for
optimum cost and performance.
This user guide contains the schematic and bill
of materials for the IR3847 evaluation board.
The guide describes operation and use of the
evaluation board itself. Detailed
application
information for IR3847 is available in the
IR3847 data sheet.
BOARD FEATURES
•
V
in
= +12V (+ 13.2V Max),
No Vcc required.
•
V
out
= +1.2V @ 0- 25A
•
F
s
=1000kHz
•
L= 0. 15uH
•
C
in
= 5x22uF (ceramic 1206) + 1x330uF (electrolytic)
•
C
out
=7x22uF (ceramic 0805)
SupIRBuck
TM