In a frequency multiplier which generates a multiple output of a reference signal, a reference signal and its inverted signal are propagated through a pair of delay circuits each including a given number of delay cells connected in cascade. The delay cells delay a signal by time t when a control signal is at a high level and delay a signal by time 2t when a control signal is at a low level. The outputs of the delay circuits are added together by an adder circuit to generate a multiple output without using a low-pass filter but by non-feedback control.