Patent ID: 9313594
Filing Date: 2016-04-12
CPC Classification: G01R,H04R

Claim Text:
1. An impedance detecting device capable of detecting the impedance value of a load, comprising: an alternating current (AC) signal generating circuit operable to generate an AC signal; an output buffer operable to generate an output voltage and an output current according to the AC signal and the impedance value of the load; a current mirror operable to generate a mirror current according to the output current; a detection impedance operable to generate a detection voltage according to the mirror current; a comparing circuit operable to generate a comparison result by comparing the output voltage with the detection voltage; and a control circuit, coupled to the comparing circuit and at least one of the current mirror and the detection impedance, operable to adjust at least one of a current ratio of the mirror current to the output current and the impedance value of the detection impedance according to the comparison result until the comparison result has satisfied a predetermined requirement.