| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress deterioration of DAC conversion accuracy caused by generation of fluctuation components in an output analog signal resulting from fluctuations in power supply voltage or the like. <P>SOLUTION: A digital/analog converter comprises: a modulator for modulating a digital signal of a plurality of bits and then converting to a pulse signal having a pulse density corresponding to a digital value; a first RZ conversion circuit for performing RZ conversion of the pulse signal based on a first clock signal to produce a first RZ pulse signal; a first integration circuit for integrating the first RZ pulse signal to output a first analog signal; a second RZ conversion circuit for performing RZ conversion of a first level signal having a specific number of first level pulse signals, based on the first clock signal, to produce a second RZ pulse signal; a second integration circuit for integrating the second RZ pulse signal to output a second analog signal; and a clock duty control circuit for controlling a duty ratio of the first clock signal in such a way that the second analog signal becomes closer to a predetermined reference level. <P>COPYRIGHT: (C)2012,JPO&INPIT |
