UPS703 Unisonic Technologies, UPS703 Datasheet - Page 6

• Manufacturer Part Number: UPS703
• Description: High Performance Current Mode Power Switch
• Manufacturer: Unisonic Technologies

UPS703
(1) Soft-Start
on current sense resistor at beginning. After V
depend on V
phase remain not end before V
V
sensed after V
T
SS
OUT
=23.8×0.47=11.2ms).
The internal reference voltages and bias circuit work at V
When every IC power on, driver output duty cycle will be decided by voltage V
Furthermore, soft-start phase should end before V
Finally soft-start also set OVP1 active phase. OVP1 active phase between 0 and V
. So the value of C
Driver
FUNCTIONAL DESCRIPTION
4.2V
4.8V
V
OUT
V
V
SS
FB
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
FB
and V
SS
reach V
CS
. The relation among V
SS
should be between 0.1μFand 4.7μF.
SS(DEACT)
T
STRAT-UP
CC
T
reach V
SOFT-START
.The Soft-start phase T
CC (MIN)
SS
SS
Fig.3 Soft-start phase
, V
during V
reach 4.2V, the whole soft-start phase end, and driver duty cycle
FB
and V
CC
CC
reach V
OUT
SS
power on, IC will enter auto-restart phase and not set up
CC
：T
as followed FIG.3.
> V
CC (MIN)
SS
THD (ON)
= 23.8×C
LINEAR INTEGRATED CIRCUIT
during V
, and shutdown at V
SS
CC
(ms) (Example: C
SS
power on. Otherwise, if soft-start
on soft-start capacitor and V
SS(DEACT)
CC
<V
, OVP1 will not be
CC (MIN)
SS
=0.47μF, then
QW-R119-015.A
.
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t
t
t
t
CS