Patent ID: 7741986

Claim:
A method for driving a pulse delay circuit that generates propagation delay for a pulse signal to be transmitted through the pulse delay circuit, comprising steps of: preparing a plurality of delay units connected to each other to be configured as the pulse delay circuit for giving the propagation delay to the pulse signal that is successively delayed by each of the delay units, each delay unit comprising plurality of transistors that include a specific transistor having first and second terminals; and driving the first and second terminals of the specific transistor with a first and second signals respectively in order to change a delay time of the each delay unit, wherein the voltages of the first and second signals are controlled separately in order to produce a change in on-resistance of the specific transistor that causes a change in the delay time of each delay unit such that the change in the on-resistance of the specific transistor is greater than that when the first and second terminal of the specific transistor are electrically tied together.