Patent ID: 8487801

Claim:
An analog-to-digital (A/D) converter, comprising: a coarse analog-to-digital (A/D) converter configured to convert, when converting an analog input signal into an N-bit digital signal, the analog input signal into a high-order m-bit digital signal; a fine analog-to-digital (A/D) converter configured to convert the analog input signal into a low-order n-bit (where n=N−m) digital signal based on a conversion result of the coarse A/D converter; and a track-and-hold (TH) circuit configured to sample the analog input signal, to supply a comparison voltage compared with a coarse reference voltage to the coarse A/D converter, and to supply a comparison voltage compared with a fine reference voltage based on a conversion result of the fine A/D converter to the fine A/D converter, wherein the TH circuit is configured to share a sampling capacitor in a selective input path for the analog input signal, the coarse reference voltage, and the fine reference voltage.