VIPER22AS STMicroelectronics, VIPER22AS Datasheet - Page 10
![IC OFFLINE SWIT PWM SMPS 8SOIC](/photos/1/38/13851/497-8-soic_sml.jpg)
VIPER22AS
Manufacturer Part Number
VIPER22AS
Description
IC OFFLINE SWIT PWM SMPS 8SOIC
Manufacturer
STMicroelectronics
Series
VIPER™r
Datasheet
1.VIPER22ADIP.pdf
(15 pages)
Specifications of VIPER22AS
Output Isolation
Isolated
Frequency Range
54 ~ 66kHz
Voltage - Input
8 ~ 50 V
Voltage - Output
730V
Power (watts)
7W
Operating Temperature
25°C ~ 125°C
Package / Case
8-SOIC (0.154", 3.90mm Width)
For Use With
497-9049 - BOARD EVAL BASED VIPER22ASTR-E497-8215 - BOARD EVAL BASED ON VIPER22A497-5864 - EVAL BOARD DUAL OUTPUT VIPER22A497-5071 - EVAL BOARD DIMMABLE HB PWR LED
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Other names
497-3287-5
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Part Number:
VIPER22AS
Manufacturer:
ST
Quantity:
20 000
Company:
Part Number:
VIPER22AS-E
Manufacturer:
EPSON
Quantity:
6 218
Part Number:
VIPER22AS/12AS
Manufacturer:
ST
Quantity:
20 000
Part Number:
VIPER22AS13TR
Manufacturer:
ST
Quantity:
20 000
Part Number:
VIPER22ASTR
Manufacturer:
ST
Quantity:
20 000
Company:
Part Number:
VIPER22ASTR-E
Manufacturer:
HOLTEK
Quantity:
500
Part Number:
VIPER22ASTR-E
Manufacturer:
ST
Quantity:
20 000
VIPer22ADIP / VIPer22AS
Figure 11 : Start Up Sequence
the regulation point where the secondary loop
begins to send a current in the optocoupler. At this
point, the converter enters a regulated operation
where the FB pin receives the amount of current
needed to deliver the right power on secondary
side.
This sequence is shown in figure 11. Note that
during the real starting phase t
consumes some energy from the V
waiting for the auxiliary winding to provide a
continuous supply. If the value of this capacitor is
too low, the start up phase is terminated before
receiving any energy from the auxiliary winding
and the converter never starts up. This is illustrated
also in the same figure in dashed lines.
10/15
V
V
V
V
OUT
DDon
DDoff
DD
I
FB
tss
ss
, the device
DD
capacitor,
t
t
t
Figure 12 : Overvoltage Sequence
OVERVOLTAGE THRESHOLD
An overvoltage detector on the V
VIPer22A to reset itself when V
V
the whole sequence of an overvoltage event. Note
that this event is only latched for the time needed
by V
resumes normal operation automatically.
DDovp
V
V
V
V
DDovp
V
DDoff
DDon
DD
DD
DS
. This is illustrated in figure 12, which shows
to reach V
DDoff
, and then the device
DD
pin allows the
DD
exceeds
t
t