Analog to digital converter protection circuit, method of controlling analog to digital converter protection circuit, and controller

摘要

An analog-to-digital converter protection circuit, a method for controlling an analog-to-digital converter protection circuit, and a controller are disclosed. The analog-to-digital converter protection circuit includes: an analog switch, an analog-to-digital converter, a controller, and a series circuit including at least two resistors connected in series. The series circuit is configured to convert a photocurrent into an analog voltage. The analog switch is configured to output, to the analog-to-digital converter, an analog voltage sampled by a conduction sampling end. A first sampling end serves as the conduction sampling end to conduct to an output end of the analog switch. The analog-to-digital converter is configured to generate a digital voltage. The controller is configured to: when the digital voltage is greater than or equal to a preset voltage threshold, output a control signal to the analog switch, to trigger the analog switch to control a second sampling end to serve as the conduction sampling end to conduct to the output end of the analog switch, where an analog voltage sampled by the second sampling end is less than an analog voltage sampled by the first sampling end; and when the digital voltage is less than the preset voltage threshold, output the digital voltage. The analog-to-digital converter can sample an analog voltage within a sampling voltage range of the analog-to-digital converter by using the foregoing circuit.