| 摘要 |
A DELTA.SIGMA type DA converter is provided with a digital circuit 21 including a PWM circuit 26 and an analog circuit 22, wherein in order to make an output of the analog circuit 22 a predetermined value, the analog circuit 22 is driven at a predetermined direct current voltage V1 (for instance, 5 V), and the digital circuit 21 is driven at a direct current voltage V2 (for instance, 3.3V) that is set lower than the direct current voltage V1. Since the digital circuit 21 and the analog circuit 22 are driven at different power supply voltages, a level shifter 23 is disposed at a boundary portion of the digital circuit 21 and the analog circuit 22, the level shifter 23 steps up a level of the PWM signal outputted from the PWM circuit 26.
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