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. 北京谱仪(BESIII)的飞行时间读出电子学(TOF)对于时间信号的测量具有非常高的要求,需要对TOF时间测量电路进行严格的测试。