DESCRIPTION

This primary controller I.C., developed in BCD60II technology, has been designed to implement off line or DC-DC power supply applications using a fixed frequency current mode control.

Based on a standard current mode PWM controller this device includes some features such as programmable soft start, IN/OUT synchronization, disable (to be used for over voltage protection and for power management), precise maximum Duty Cycle Control, 100ns leading edge blanking on current sense, pulse by pulse current limit, overcurrent protection with soft start intervention and ”constant power” function for cotrolling throughput power in multisync monitor SMPS.

■ CURRENT-MODE CONTROL PWM

■ SWITCHING FREQUENCY UP TO 1MHz

■ LOW START-UP CURRENT (< 120µA)

■ CONSTANT OUTPUT POWER VS. SWITCHING FREQUENCY

■ HIGH-CURRENT OUTPUT DRIVE SUITABLE FOR POWER MOSFET (1A)

■ FULLY LATCHED PWM LOGIC WITH DOUBLE PULSE SUPPRESSION

■ PROGRAMMABLE DUTY CYCLE

■ 100AND 50 MAXIMUMDUTY CYCLELIMIT

■ PROGRAMMABLE SOFT START

■ PRIMARY OVERCURRENT FAULT DETECTION WITH RE-START DELAY

■ PWM UVLO WITH HYSTERESIS

■ IN/OUT SYNCHRONIZATION

■ LATCHED DISABLE

■ INTERNAL 100ns LEADING EDGE BLANKING OF CURRENT SENSE

■ PACKAGE: DIP16 AND SO16N