| 摘要 |
PROBLEM TO BE SOLVED: To reduce nonlinear errors in a local digital analog conversion circuit, etc., for outputting an analog signal corresponding to a multi-level with a relatively simple configuration. SOLUTION: An analog signal output circuit comprises two unit analog circuits B1 and B2 for outputting an analog signal corresponding to a level "-1" or "1" and a low pass filter (LPF) for smoothing and outputting an analog signal outputted from the two unit analog circuits B1 and B2 selected in accordance with a code outputted from a four-valuedΔΣmodulator. When an input signal is -2 or +2, outputs of the unit analog circuits B1 and B2 are added to output an analog signal corresponding to -2 or +2. When an input signal is -1 or +1, the unit analog circuits B1 and B2 are alternately used to output an analog signal corresponding to -1 or +1, thereby reducing nonlinear errors caused by variations in analog elements. COPYRIGHT: (C)2005,JPO&NCIPI
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