The STMicroelectronics Controller, it belongs to family of control ICs provides the necessary features to implement off-line or DC to DCfixed frequency current mode control schemes with a minimal external parts count. Internally implemented circuits include a trimmed oscillator for precise DUTY CYCLE CONTROL under voltage lockout featuring start-up current less than 0.5mA, a precision reference trimmed for accuracy at the erroramp input, logic to insure latched operation, a PWM comparator which also provides current limit control, and a totem pole output stage designed to source or sink high peak current.

Internally trimmed reference with undervoltage lockout
High current totem pole output
Undervoltage lockout with hysteresis
Low start-up and operating current