| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a ΔΣ modulator capable of using an area with a more excellent linearity in an integrator even when inputting a differential input signal where a code is positive or negative, and to provide a ΔΣ type A/D converter. Ž<P>SOLUTION: The ΔΣ modulator includes: a subtractor 21 for outputting a value obtained by subtracting a feedback signal from an analog input signal; the integrator 12 having a differential amplifier for amplifying and outputting the output signal of the subtractor 21; a quantizer 15 for outputting a value obtained by comparing the output signal of the integrator 12 with a prescribed threshold; and a delay device 16 for delaying the output signal of the quantizer 15 so as to convert the output signal of the quantizer 15 into the feedback signal. The ΔΣ modulator includes an offset voltage generating circuit 1 for generating an offset voltage to move the amplitude center of the output signal of the integrator 12 to zero or substantial zero by offsetting the threshold. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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