The measurement of time signals in flight time readout (TOF) electronics of the third modification project of Beijing Spectrometer (BESIII) is very difficult according to the very high-resolution request

so we need to strictly test the design of the circuit for time measurement. This paper introduces the design of a high accurate signal generator circuit for this testing

which can generate pulse signal with the jitter less than 23.623 ps and clock signal with the jitter less than 12.265 ps. And two pivotal technologies

i.e. the designs of high-speed

high-resolution clock circuits and pulse generator circuits are discussed in this paper too.