VIPER12A-E Datasheet, PDF (1/21 Pages) STMicroelectronics – Low power offline switched-mode power supply primary switcher

VIPER12A-E
Low power offline switched-mode power supply primary switcher
Features
■ Fixed 60 kHz switching frequency
■ 9 V to 38 V wide range V_DD voltage
■ Current mode control
■ Auxiliary undervoltage lockout with hysteresis
■ High voltage start-up current source
■ Overtemperature, overcurrent and overvoltage
protection with auto-restart
■ Typical power capability
– European (195 - 265 Vac) 8 W for SO-8,
13 W for DIP-8
– European (85 - 265 Vac) 5 W for SO-8,
8 W for DIP-8
Description
The VIPER12A combines a dedicated current
mode PWM controller with a high voltage power
MOSFET on the same silicon chip.
Figure 1. Block diagram
SO-8
DIP-8
Typical applications cover off line power supplies
for battery charger adapters, standby power
supplies for TV or monitors, auxiliary supplies for
motor control, etc.
The internal control circuit offers the following
benefits: Large input voltage range on the V_DD pin
accommodates changes in auxiliary supply
voltage (This feature is well adapted to battery
charger adapter configurations), automatic burst
mode in low load condition and overvoltage
protection in HICCUP mode.
DRAIN
REGULATOR
INTERNAL
SUPPLY
VDD
FB
_
8/14.5V ₊
+
42V ^_
ON/OFF
60kHz
OSCILLATOR
OVERTEMP.
DETECTOR
S
R1 FF Q
R2 R3 R4
PWM
LATCH
OVERVOLTAGE
R
LATCH
S ^FF Q
BLANKING
+
_ _{0.23 V}
1 kΩ
230 Ω
SOURCE
December 2010
Doc ID 11977 Rev 2
1/21
www.st.com
21