| 摘要 |
PURPOSE:To perform conversion of high resolution with a small number of comparators, by repeatedly operating plural comparators when an analog signal is converted into a digital signal. CONSTITUTION:In the first place, a switch (S) 18 is set to the (a) side by a clock source 17 and signals from an analog signal input section 13 are inputted in (n) sets of comparators 14. In the remaining input section of the comparators 14 a reference voltage produced by a power source 11 and series resistance 12 is inputted and the compared result between the signals and reference voltage is inputted in a shift register 22 through an encoder 21 after respectively passing through AND circuits 15. The output of the AND circuits 15 controls (n) pieces of Ss 16, selects a reference voltage to be inputted in the comparators 14, and inputs the selected reference voltage in a differential amplifier 19. The amplifier 19 amplifies a value which is obtained by subtracting one of reference voltages from a value outputted from a delay circuit 20 by (n+1) times and outputs the amplified result. Then the S 18 is set to the (b) side by the clock source 17 and the output of the amplifier 19 is made to be inputted. This operation is repeated for (m) times and, as a result, conversion of high resolution can be performed. |
