VIPER27 STMicroelectronics, VIPER27 Datasheet - Page 16

• Manufacturer Part Number: VIPER27
• Description: VIPerPlus family: fixed frequency high performance off line high voltage converter
• Manufacturer: STMicroelectronics

Operation descriptions
16/31
Figure 23. Timing diagram: normal power-up and power-down sequences
Figure 24. Soft-start: timing diagram
V
V
I
DRAIN_START
DD(RESTART)
DDch
V
DRAIN
V
(3mA)
V
DDoff
DDon
V
V
I
DD
DD
IN
Power-on
I
DRAIN
V
V
V
I
V
FBolp
Dlim
FBlin
OUT
FB
t
SS
( SOFT START- UP )
Doc ID 15133 Rev 5
Normal operation
DELAY (OLP)
STEADY STATE
regulation is lost here
Power-off
V
HV startup is no more activated
t
t
t
IN
< V
DRAIN_START
time
time
time
time
VIPER27