Hi Expert,
My customer traditionally use UC2845 as the controller for buck topo, the input voltage is 200V, output range is 80V to 160V, output current is around 15A. Now they need a new controller which can achieve synchronous buck to improve the efficiency. Could you please recommend a suitable device for this design? Thanks!
Regards,
Jared
Hi Jared,
Sync buck PWM controllers are going to be limited to battery voltage or telecom voltage and will only be rated up to 100V max. How about keeping the UC284x and using it's single PWM output as the input to UCC20225A-Q1. You are basically using a single PWM input, setting an acceptable dead time and generating a corresponding D, 1-D output that could drive external MOSFETs rated to any voltage. The UCC20225A has dual isolated independent output drive stages so that one can be floating high-side using a simple bootstrap technique while the other can be ground reference for driving the low side, sync FET. Typical diagram for the sync buck is shown below, where the μC would be replaced by the UC284x.
Regards,
Steve M
