| 摘要 |
PURPOSE:To suppress an ideal quantization error within + or -LSB/2 without using a reference voltage of different polarity by providing a means forming a pseudo input, an output comparator, a correction memory, a successive comparison register and a means increasing the code of the successive comparator register by 1 so long as the content of the correction memory is 1. CONSTITUTION:A comparator CMP being a means forming a pseudo input quantity subtracting a value equivalent to LSB/2 from an input quantity to a DA converter compares the pseudo input quantity aud an output of the DA converter. Then the result is discriminated while codes of the DA converter are all 0. A value representing the absolute value of the input quantity larger by LSB/2 as 1 and smaller by it as 0 is stored in a correction memory. Only with the content of the correction memory set to 1, the digital code of the successive comparison register is incremented by 1. Thus, the ideal quantization error is kept within + or -LSB/2 without using a reference voltage of different polarity.
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