Soft Start Circuit - Epson S1F76540M0C Series Technical Manual

5. FUNCTIONAL DESCRIPTION

5.6 Soft Start Circuit

The soft start circuit is used to minimize the peak value of the rush current at startup of the booster.
As shown in Figure 5.5, the maximum 200 ms (100mSec Typ.) after the input voltage VI has been input is set as
the soft start period. During the soft start period, the VO output may not reach the electric potential that was
boosted sufficiently.
In this case, the electric potential of the VO output is boosted smoothly up to the specified voltage after the soft
start period has been expired.
Input voltage VI
Booster voltage VO
Stabilization output
V Regulator VI
REG
[Notes on connecting the capacitor for stabilizing the input voltage]
To stabilize the input voltage VI, the capacitor (CI) to be connected between the V
placed near the IC pin so that the wiring is as short as possible.
10
Soft start time
Typ. 100mSec
Max. 200mSec
Figure 5.5 Soft start operation
EPSON
and VI pins must be
DD
S1F76540M0C Series Technical Manual
(Rev.1.1)