TheUC384xB family ofcontrolICs providesthe necessary features to implement off-line or DC to DC fixed 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 lockoutfeaturingstart-up current less than0.5mA,a precision reference trimmed for accuracy at the error amp input, logicto insure latched operation,a PWM