Semiconductor integrated circuit incorporating photo detectors

摘要

In response to a test signal received at a test terminal, one terminal of a first computation circuit and three terminals of a second computation circuit are each provided with a reference voltage, or a ground potential, which is available at reference voltage supply terminals associated with photo detectors. Another terminal of the first computation circuit and the second computation circuit are each provided with a detected voltage. If the functions of the computation circuits are not defective, function signals will be obtained each having a value which corresponds to an imbalance between the detected voltage and the reference voltage. Thus, only one test terminal is required, which reduces the size of the semiconductor integrated circuit.