Abstract: A kind of highly distinguishable 4-circuit race answering device is designed with a series of commonly used intergarted circuit of 74.The device is all-digital design,which is benifical to devide more groups and resolute signals.In addition to the basic function of rece answering.It also has some other advantages such as the capital of pirority,the function of timing and reset .when using it,the moderator can control the switch to fulfil its function of timing and reset. The circuit is mainly composed by the 4D latch ,the non-gate contolled by ringlike oscillator,the logic controlled circuit and the timing circuit .The oscillator has no connection with any oher component and it just brings about vibartion through the delay of circuit.So,the frequency of its vibartion is very high,which offer conditions to improve the speed of distinguishing time among group.
Key words: Race answering device; Integrated circuit; Timing circuit ; Latch; Ring oscillator