RM3253

RM3253 RM3253 Off Line AC/DC Switcher IC Description The RM3253 series switcher ICs cost effectively replace all power supplies up to 5W output power based on unregulated isolated linear transformer (50/60HZ). Unlike conventional PWM (pulse width modulation) controllers, they regulate the output voltage in a new method of off-time modulation control. The controller consists of a VCO (voltage control oscillator), Sense and logic circuit, VDD pin, under-voltage lockout circuit, protection for over-voltage, current limited circuit, leading edge blanking, over load protection and fault condition auto-restart. They are ideal low power AC/DC adapter/charger solution for portable devices, Features Built-in 800V high voltage BJT and minimal external componets Low start-up current: Typ.15 μA Max.25 μA UVLO(under voltage lockout):Typ.12V start-up Typ.6V shut-down Low operating current:Typ.2 mA Max.5 mA LEB(leading edge blanking): Typ.300ns OVP(over voltage protection)...