| 摘要 |
PROBLEM TO BE SOLVED: To provide a D/A converter of a current output type with high accuracy. SOLUTION: The potential of sources of n-pieces of output transistors M1 is fixed by a common fixed voltage GND, and the sources are connected to a current output terminal 102. The drain and the gate of an input transistor M2 are commonly connected to those of the output transistors M1. A first current voltage conversion section 14 is connected to the drain side of the input transistor M2 to convert a current Im2 flowing through the input transistor M2 into a voltage Vx1. A second current voltage conversion section 16 converts a reference current Iref into a voltage Vx2. A first error amplifier 12 receives the voltages Vx1, Vx2 to regulate the gate voltage of the input transistor M2 and the output transistors M1. On a path where the output of the first error amplifier 12 reaches the gates of the output transistors M1, n-pieces of switches SWs are provided. A control section 30 controls ON/OFF of the switches SWs in response to a digital signal DIG. COPYRIGHT: (C)2008,JPO&INPIT
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