| 摘要 |
PURPOSE:To enable two functions of A/D and D/A converters, by switching an output of a sequential comparison register and an input to be D/A-converted. CONSTITUTION:Between an output line of a sequential comparison register 30 and a D/A converter 10, a plurality of switch circuits 5-7 which can be switched by an operating selection signal are provided. At the A/D converting operation, the sequential comparison register 30 is connected to the D/A converter 10, D/A converting operation switch circuits 5-7 are switched to opposite side, the input of the D/A converter 10 is connected only to a digital output terminal 8, and the digital output terminal 8 is usable as the input pins for D/A conversion. An operational amplifier 9 is required for D/A converting operation only and it is connected with external pins. |
