| CPC H03M 1/1245 (2013.01) | 18 Claims | 

| 
               1. An analog-to-digital conversion circuit, comprising: 
            a first conversion circuit, configured to convert an original analog signal to obtain a first digital signal with a first bit width; 
                at least one voltage division circuit, each voltage division circuit among which is configured to divide a voltage of a first-stage analog signal to obtain a second-stage analog signal, wherein the first-stage analog signal is the original analog signal or a second-stage analog signal output by a previous voltage division circuit adjacent to the voltage division circuit; 
                a second conversion circuit corresponding to the voltage division circuit, configured to convert the received second-stage analog signal according to a preset algorithm to obtain a second digital signal with a second bit width; and 
                a control calculation circuit, configured to obtain a target digital signal with a third bit width according to the first digital signal and the second digital signal; 
                wherein the third bit width is larger than the first bit width, and the third bit width is larger than the second bit width; and 
                wherein each voltage division circuit comprises a plurality of voltage division resistors, and a first switching transistor corresponding to each voltage division resistor; 
                the plurality of voltage division resistors are connected in series; 
                in the voltage division resistors which are connected in series, a first end of each voltage division resistor is connected with a first end of the corresponding first switching transistor; 
                second ends of the first switching transistor are connected to each other and a second end of each first switching transistor is connected to the second conversion circuit corresponding to the voltage division circuit, and a control end of each first switching transistor is connected to the control calculation circuit; and 
                a first end of a first voltage division resistor is used for inputting the first-stage analog signal, and a second end of a last voltage division resistor is grounded. 
               |