| 摘要 |
PURPOSE:To reduce influences of differential nonlinearity, for example, a linear arch fact or the like by generating random numbers consisting of the same number of bits as an input digital signal to be subjected to analog conversion and subjecting the signal to digital-analog conversion by digital subtraction and adding analogically this conversion result to the output obtained by direct digital- analog conversion. CONSTITUTION:The digital signal is latched in the first latch circuit 3, and pseudo random numbers having the same number of bits as the digital signal are latched in a latch circuit 5. The latch circuit 3 outputs I, and the latch circuit 5 outputs R, and a digital subtracting means 7 subtracts digitally random numbers R from the digital signal I, and the subtraction result is converted analogically by a D/A converter 8. A D/A converter 9 to which only pseudo random numbers R are inputted through the latch circuit 5 converts R to an analog value, and outputs of converters 8 and 9 are added by an analog adding means 10. An average value of repeated analog conversions is operated to reduce influences of differential nonlinearity statistically. |
