DESCRIPTION

The UC384xA family of control ICs provides the necessary features to implement off-line or DC to DC fixed frequencycurrent mode control schemes with a minimal external parts count. Internally implemented circuits includea trimmed oscillator for precise DUTY CYCLE CONTROL under voltage lock out featuring start-up current less than0.5mA,a precision reference trimmed for accuracy at the error amp input,logic to in sure latched operation,a PWM comparator which also provides current limit control, and a totem pole output stage designed to source or sink high peakcurrent.The output stage,suitable

for driving N-Channel MOSFETs, is low in the off state.

. TRIMMED OSCILLATOR DISCHARGE CURRENT

. CURRENT MODE OPERATION TO 500kHz

. AUTOMATIC FEED FORWARD COMPENSATION

. LATCHING PWM FOR CYCLE-BY-CYCLECURRENT LIMITING

. INTERNALLY TRIMMED REFERENCE WITH UNDERVOLTAGE LOCKOUT

. HIGH CURRENT TOTEM POLE OUTPUT

. UNDERVOLTAGE LOCKOUT WITH HYSTERESIS

. LOW START-UP CURRENT (< 0.5mA)

. DOUBLE PULSE SUPPRESSION