Current-voltage conversion circuit and method, integrator and analog-to-digital converter

The invention discloses a current and voltage conversion circuit and method, an integrator and an analog-to-digital converter, a current scaling control unit is configured between an input circuit unit and an output circuit unit of the current and voltage conversion circuit, the input current can be adaptively scaled according to a set current gear, and the current scaling control unit is used for scaling the input current. And the output circuit unit is used for converting the intermediate current into an output voltage signal. Wherein the current scaling control unit comprises a front operational amplifier and a multi-stage current mirror branch circuit, the multi-stage current mirror branch circuit is configured with output of a plurality of current gears, and the current gear can be selected and set from the plurality of current gears according to needs. Therefore, self-adaptive scaling is carried out on the input current through the multi-stage current mirror branches with the set number and width, and f