Advanced Member level 5
Hello, I'm going to try to make a high-bandwidth class D amp for AM modulating RF amplifiers. For best bandwidth (at least 300KHz), I'm want to use a synchronous buck regulator, with an operating frequency around 2MHz or higher. I need to vary the output voltage setpoint with a control voltage, but most PWM controllers have a fixed setpoint internally, so they won't work. Does anyone know of a high speed controller where the setpoint voltage can be varied? Ideally I'd like something like the UC3824, where all the error amplifier pins are available, but that chip isn't fast enough for my needs. The controller doesn't necessarily need to have current-mode control capabilities.