Transfer circuit for defect inspection of an integrated circuit

摘要

A logic circuit is formed on a gate array chip together with a custom-circuit. Bonding pads mounted on the gate array chip are used as the terminals which send forth or receive data and control signals. The logic circuit is provided with a shift register for holding data to test the flip-flops of the custom-circuit and output data from the flip-flops. The shift register comprises the stages each of which holds 1-bit data selected by a read control signal. The output terminals of the stages are respectively connected to the input terminals of the flip-flops of the custom-circuit through the AND gates which are rendered conducting in response to a set control signal. The output terminals of the flip-flops are connected to the input terminals of the respective stages of the shift register.