Abstract: The scan test circuit disclosed has a first input terminal and a second input terminal for respectively inputting first data of one bit and second data as serial data, a third input terminal for inputting an operation switching signal for determining a scan operation and a normal operation, an input selector for selecting either the first data or the second data in response to the supply of the operation switching signal and outputting the selected data, a register for holding the selected data as hold data, a first output terminal for outputting first output data, and a second output terminal for outputting second output data. The scan test circuit includes a latch circuit which latches a shift mode signal and generates an operation switching latch signal. A selector selectively outputs either an input data or an input data as a selected signal in response to the supply of the signals.

Abstract: A power converter converts AC input power into AC output power to which a load is connected. This power converter comprises a controller for controlling power converting operation of the power converter, a DC voltage detector for detecting a DC voltage of the DC power to provide a DC voltage signal, a first reference generator for generating a first reference, an output detector for detecting a condition of the AC output power to provide an output condition signal, a second reference generator for generating a second reference in response to the output condition signal, a condition detector for detecting a condition of the AC input power to provide an output condition signal, and a selector for supplying the second reference to the controller when the input condition signal is provided.