Current source cell used in current segment type D to A converter

摘要

A segment control type D to A converter includes a decoder and a plurality of current source cells. The decoder decodes a digital input signal to generate a control signal. The plurality of current source cells are selected by the control signal output from the decoder. A current output from the selected current source cell is output from an output terminal. Each of the current source cells includes first and second transistors. One terminal of the current path of the first transistor is connected to a constant current source, and the first transistor is ON/OFF controlled such that the gate of the transistor receives the control signal output from the decoder. One terminal of the current path of the second transistor is connected to the other terminal of the current path of the first transistor, and the other terminal of the second transistor is connected to the output terminal. A reference voltage is applied to the gate of the second transistor to cause the second transistor to be normally set in an ON state.