Iterative Balancing Algorithm for Multistage DC Amplifiers

The article describes a simple implementation of the algorithm for calculating the offset voltage compensation at the output of digitally controlled programmable DC amplifiers that form a single multistage measuring path. The article presents the calculation of the bias voltage based on the analytical model of the amplifying circuit, a balancing mechanism based on an external control system is proposed. The main result of the algorithm is to find the optimal values of the control codes of the electronic potentiometers for each stage, which ensure that the voltage at the amplifier output is close to zero at a known measured value of the bias voltage at the input or output of the first amplifier stage. The advantage of the algorithm is the simplicity of implementation, the absence of current overloads of electronic potentiometers during the balancing of the measuring path as a whole, a wide range of variation of the parameters of the amplifying stages.