HA16114P

HA16114P/PJ/FP/FPJ, HA16120FP/FPJ Switching Regulator for Chopper Type DC/DC Converter Description The HA16114P/FP/FPJ and HA16120FP/FPJ are single-channel PWM switching regulator controller ICs suitable for chopper-type DC/DC converters. Integrated totem-pole output circuits enable these ICs to drive the gate of a power MOSFET directly. The output logic of the HA16120 is designed to control a DC/DC step-up (boost) converter using an N-channel power MOS FET. The output logic of the HA16114 is designed to control a DC/DC step-down (buck) converter or inverting converter using a P-channel power MOS FET. These ICs can operate synchronously with external pulse, a feature that makes them ideal for power supplies that use a primary-control AC/DC converter to convert commercial AC power to DC, then use one or more DC/DC converters on the secondary side to obtain multiple DC outputs. Synchronization is with the falling edge of the ‘sync’ pulse, which can be the secondary output pulse from a flyback transformer. Synchronization eliminates the beat interference that can arise from different operating frequencies of the AC/DC and DC/DC converters, and reduces harmonic noise. Synchronization with an AC/DC converter using a forward transformer is also possible, by inverting the ‘sync’ pulse. Overcurrent protection features include a pulse-by-pulse current limiter that can reduce the width of individual PWM pulses, and an intermittent operating mode controlled by an on-off timer. Unlike t...