R-2R network automatic error elimination circuit and method for ion source control circuit

The invention relates to an R-2R network automatic error elimination circuit and method used in an ion source control circuit, and aims to solve the technical problems that the ion source control is easy to deviate and the manual adjustment is inconvenient due to the existence of errors in an air pressure control circuit. The error circuit comprises a threshold voltage unit, a positive deviation discriminator, a negative deviation discriminator, a clock unit, a positive deviation counting unit, a negative deviation counting unit, a presettable add-subtract counter, a counting control unit and an R-2R network unit. The method comprises the following steps: 1, starting a circuit, and adjusting a presettable add-subtract counter to a base value; 2, the deviation discrimination unit compares the received voltage signals; and the presettable add-subtract counter is adjusted by adjusting the deviation screening unit and the deviation counting unit, so that the digital quantity of the presettable add-subtract counte