Patent ID: 8081096

Claim:
A signal generating apparatus comprising: a DA converter that outputs an output signal comprising an output voltage corresponding to input data supplied thereto; a comparing section that compares (i) a level of a signal output from an analog circuit that propagates the output signal to output a signal corresponding to the input data to (ii) a level of the signal output by the DA converter; and a control section that adjusts the output signal of the DA converter based on a comparison result of the comparing section; and a sample/hold unit that is provided between the DA converter and an output end of the signal generating apparatus, and that samples an output voltage of the DA converter and holds the sampled output voltage, wherein during a holding period in which the sampled output voltage is held, the control section (i) provides the DA converter with comparison data instead of the input data to cause the DA converter to output a comparison voltage corresponding to the comparison data, (ii) causes the comparing section to compare a voltage of the signal output by the analog circuit to the comparison voltage, and (iii) adjusts the output voltage of the DA converter according to the input data based on a comparison result of the comparing section.