D/A CONVERTER AND SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To reduce the current consumption by preventing a reference voltage being a center level of an outputted voltage from being generated from an amplifier. SOLUTION: A resistance circuit 1 divides a power supply voltage and outputs a plurality of voltages proportional to each other. A decoder circuit 3 decodes a digital signal and outputs a control signal. A switch circuit 2 is turned ON / OFF depending on the control signal from the decoder circuit 3 to select and output the voltage outputted from the resistance circuit 1. A conversion circuit 4 gives a medium voltage of the power supply voltage resulting from dividing the power supply voltage by resistors to an inverting input terminal of an operational amplifier 4a configuring a noninverting amplifier circuit and the operational amplifier 4a outputs a voltage received at a noninverting input terminal of the operational amplifier 4a so that the output voltage swings around the medium voltage. Thus, an amplifier for outputting the medium voltage is not needed and the current consumption can be reduced. COPYRIGHT: (C)2005,JPO&NCIPI