The LT4430 drives the optocoupler that crosses the galvanic barrier in an isolated power supply. The IC contains a precision-trimmed reference, a high bandwidth error amplifier, an inverting gain of 6 stage to drive the optocoupler and unique overshoot control circuitry. The LT4430's 600mV reference provides 0.75% initial accuracy and 1.25% tolerance over temperature. A high bandwidth 9MHz error amplifier permits simple frequency compensation and negligible phase shift at typical loop crossover frequencies. The optocoupler driver provides 10mA of output current and is short-circuit protected. A unique overshoot control function prevents output overshoot on startup and short-circuit recovery with a single capacitor.