| 摘要 |
PURPOSE:To match the period of the synchronous pulse with the operating period of test, by constituting the test equipment with the trigger pulse generation circuit, pattern generation circuit, shift register, clock pulse generation circuit and pulse period control circuit. CONSTITUTION:The trigger pulse TG from the trigger pulse generation circuit 6 is taken as start input, and the synchronous pulse SYNC produced from the pattern generation circuit 1 has the delay time t1 to the pulse TG. The clock pulses phi1 to phi3 from the clock pulse generating circuit 4 to the shift register 3 have the delay time of t2 to t4 to the pulse TG, to set the relation of t1>t4>t2>t3. The readout period of the tested device 2 TR and the write-in period TW are respectively set to theregisters 9a and 9b. The pulse SYNC and the pattern signal POUT are outputted from the circuit 1 with the initial pulse TG, and the first pulses phi1 to phi3 are made ineffective because they are ahead the synchronous pulse, the write-in instruction W is set with the second pulse, and the period of the pulse TG is made agreed with the write-in period TW with the third pulse. |
