| 摘要 |
PROBLEM TO BE SOLVED: To provide a D/A converter with offset compensating function and an offset compensation method of the D/A converter for canceling DC offset held by a comparator itself to be used for DC offset compensation of the D/A converter and for realizing an exact DC offset compensation of the D/A converter. SOLUTION: An input changeover switch 40 is provided at a front stage of the comparator 50 which measures the DC offset of the D/A converter 30 and in addition, a selective polarity inversion device 60 is provided at a rear stage. A first compensation value is generated by a compensation value generation circuit 12 and stored in a register 18. Next, a second compensation value is generated by switching the input changeover switch 40 and the polarity inversion device 60 and stored in a register 20. Then, a third compensation value is calculated by taking an average of the first and second compensation values by a compensation value calculation circuit 22 and the DC offset of the D/A converter 30 is compensated by the compensation value. COPYRIGHT: (C)2004,JPO&NCIPI
|
