MEASURING INSTRUMENT FOR LOGIC INTEGRATED CIRCUIT

摘要

PURPOSE:To prevent plural DUTs (correcting circuit element to be measured) from malfunctioning owing to wiring capacity by supplying an input signal which is restored accurately by using a latch signal right before the input terminal of a DUT to the input terminal of each DUT. CONSTITUTION:A clock generating device 1 is connected to the input terminal D of s shift register 3 through a frequency divider 2. The output CKphi of the device 1 is supplied to the shift pulse input terminal SP of the register 3 to obtain shift pulses. The register 3 shifts a signal to the terminal D with a signal to the terminal SP and outputs the signal. Output terminals Sphi and S1-Sn are selected with a switch 4 and the signal of the selected terminal is supplied as a latch pulse CKD to CK terminals of FFs Fphi and Fe-Fn. Input signals Aphi and Al-An from a signal source to D terminals of the FFs Fphi and FlnFn are latched with pulses CKD and outputted from output terminals Qo and Ql-Qn as output signals AXphi and Qn. Consequently, the signals which are waveform-shaped right before the input terminals of the DUTs, which are then prevented from malfunctioning.