Ring Generator Controls Output Power Circuits

Well suited for low-cost, high-volume, high-performance sinewave ring generator applications requiring from less than 1W to 6W of output power, the PD-5019 Ring Generator Controller is a digital PWM controller that provides all the necessary control signals for implementing overload and short-circuit protection, zero-crossing relay synchronization, off-hook detection, and output amplitude (45 to 95 VRMS) and frequency selection (16.7, 20, 25 and 50 Hz). Designed to be used with an open-loop flyback topology, this controller drives a minimal component count for the final design and operates simply from a single 5V supply. The device generates a PWM signal that drives an FET that switches the primary of a flyback transformer, and an additional control signal synchronizes a four-output transistor bridge that converts the half sinewave to a full sinewave.