Abstract: Disclosed is a dual transistor flyback converter having a pair of synchronously driven switching transistors (20, 36) for switching voltage to a primary (12) of a flyback transformer (10). When driven into a cutoff state, transistor (36) isolates switching transistor (20) from the supply voltage (V1), thereby preventing a transformer reflected voltage from being superimposed on the supply voltage and imposing such voltage across the transistor (20). Clamp diodes (40, 42) maintain the switching transient voltage across the flyback transformer primary (12) between prescribed limits. Capacitor (48) allows the switching transient to pass and be clamped by the diodes (40, 42), but prevents the reflected secondary voltage from being clamped when the input voltage is low.