DIGITAL-ANALOG CONVERTING CIRCUIT

摘要

PURPOSE:To attain the standardization of a board by applying an external reference voltage required for a D/A converter externally from the board to increase the degree of freedom of the reference voltage applied to the converter. CONSTITUTION:The D/A converting circuit 4 is mounted on the board 1 and a digital signal from a device 2 such as a microcomputer is inputted to a digital input terminal 3 of the converting circut 4. An output from an analog output terminal 5 of the converting circuit 4 is outputted to analog signal output terminal 6 of the board 1. Further, a reference voltage input external terminal 10 of the board 1 is connected to a reference voltage input terminal 7 of the converting circuit 4 and the reference voltage from a reference voltage source 8 is fed to the external terminal 10 from a reference voltage selecting terminal 9. Then the reference voltage applied to the converting circuit 4 is fed from the outside of the board 1 to increase the degree of freedom of the reference voltage applied to the converting circuit 4 thereby attaining the standardization of the board 1.