International Rectifier SupIRBuck IRDC3846, User Manual, Page: 7 / 14

IRDC3846-P1V2
Confidential
This evaluation board is a preliminary version meant for the engineering evaluation of the IR3846. Based on the results
of the continuing evaluation, this board can evolve and change without notice
AL
4/11/2013 7
TYPICAL OPERATING WAVEFORMS
Vin=12.0V, Vo=1.2V, Io=0A-35A, Fsw=600kHz, Room Temperature, No air flow
Fig. 5: Output Voltage Ripple, 35A load
Ch
1
: V
o
Fig. 6: Inductor node at 35A load
Ch
2
:LX
Fig. 7: Short (Hiccup) Recovery
Ch
2
:V
o
, Ch
3
:PGood, Ch
4
:I
o
Fig. 3: Start up at 35A Load
Ch
1
:V
in
, Ch
2
:V
o
, Ch
3
:PGood, Ch
4
:V
cc
Fig. 2: Start up at 35A Load
Ch
1
:V
in
, Ch
2
:V
o
, Ch
3
:PGood, Ch
4
:Enable
Fig. 4: Start up with 1.08V Pre Bias, 0A Load
Ch
2
:V
o
, Ch
3
:PGood