| 摘要 |
PURPOSE:To decrease a distortion due to error at a zero cross point by adjusting a current value of an MSB of a sequential comparison reference current source equally to the total sum of current values of reference current sources to elminate the need for trimming. CONSTITUTION:A current value of the comparison reference current sources 1- N of a converter 7 is sequentially to I, I/2, I/2<2>-I/2N<-1> and the current value of the MSB is changed so that a voltage difference between an output of a sample hold circuit 16 of the current value of the MSB turning on a switch 3 only and an output of a sample hold circuit 17 of a current total sum of the LSB turning on all switches 4 except the switch 3 is zero. Thus, the erroneous distortion at the zero point of the analog signal is decreased without trimming. |
