Residue transfer loop, successive approximation register analog-to-digital converter, and gain calibration method

Abstract

A residue transfer loop, a successive approximation register analog-to-digital converter and a gain calibration method are disclosed. In particular, the residue transfer loop includes a sampling switch module, a logic controlling circuit, a residue holding capacitor module, a DAC capacitor array, a residue transfer module, a current rudder, a reset switch module and a charge sharing switch module. The logic controlling circuit sequentially outputs control signals according to preset time intervals in a preset period to control the reset switch module, the residue transfer module, the sampling switch module and the charge sharing switch module to work sequentially, thereby realizing a residue transfer.