VIPER12ADIP-E

VIPER12A-E Low power offline switched-mode power supply primary switcher Features ■ Fixed 60 kHz switching frequency ■ 9 V to 38 V wide range VDD 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 VDD 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 Contents Contents VIPER12A-E 1 Electrical data . . . . . . . . . . . . . . . . . . . . . . . . . . ....