A switched mode power supply controller includes a latch having an output for providing a drive signal, an off-time control circuit operating in valley switching and frequency reduction modes controlling an off-time of the latch based on at least a zero current detect signal, and an on-time control circuit resetting the latch in response to a current sense signal exceeding a feedback voltage representative of a load and to the current sense signal exceeding a modulated peak current threshold value. The on-time control circuit resets the latch in response to a current sense signal exceeding a feedback voltage representative of a load and to the current sense signal exceeding a peak current threshold value. In the frequency reduction mode, the on-time control circuit modulates the peak current threshold value by increasing the peak current threshold value by a predetermined amount.