| 摘要 |
PURPOSE:To obtain a DA converting circuit with high performance at low cost, by varying the signal range of an input digital signal supplied to the DA converter on the basis of an information range signal. CONSTITUTION:While an input digital signal supplied to an input terminal 1 is shifted in a shift register SR, a signal which shows the information range of the input digital signal is obtained. Then, input information which corresponds to the information range of the input digital signal is supplied to a DA converter DAC1 and a range bit is generated on the basis of said signal showing the information range and then supplied to a DA converter DAC2, thus obtaining an external reference input signal to the DA converter DAC1 as the output of the DA converter DAC2. Therefore, polygonal expansion operation is performed easily with the simple constitution. |
