IRDC3821
Rev 0.1
01/07/2008
1
USER GUIDE FOR IR3821 EVALUATION BOARD
DESCRIPTION
The IR3821 is a synchronous buck
converter, providing a compact, high
performance and flexible solution in a small
5mmx6mm Power QFN package.
Key features offered by the IR3821 include
programmable soft-start ramp, precision
0.6V reference voltage, programmable
Power Good
,
thermal protection, fixed
600kHz switching frequency requiring no
external component, input under-voltage
lockout for proper start-up, and pre-bias
start-up.
An 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 IR3821 evaluation board.
The guide describes operation and use of the
evaluation board itself. Detailed application
information for IR3821 is available in the
IR3821 data sheet.
BOARD FEATURES
•
V
in
= +12V (13.2V Max)
•
V
out
= +1.8V @ 0- 7A
•
L=1.0uH
•
C
in
=3x10uF (ceramic 1206) + 330uF (electrolytic)
•
C
out
=6x22uF (ceramic 0805)
Sup
IR
Buck
TM
