Analog-To-Digital Converter Protection Circuit, Method for Controlling Analog-To-Digital Converter Protection Circuit, and Controller

An analog-to-digital converter protection circuit, comprising:

• an analog switch;
• an analog-to-digital converter;
• a controller;
• and
• a series circuit;
• wherein the series circuit comprises a plurality of resistors connected in series;
• wherein a head end of the series circuit is configured to be connected to an output end of a bi-directional optical sub-assembly (BOSA), a tail end of the series circuit is configured to be grounded, a ground-distant end of each resistor in the series circuit is connected to a different sampling end of the analog switch, an output end of the analog switch is connected to an input end of the analog-to-digital converter, an output end of the analog-to-digital converter is connected to an input end of the controller, and a first output end of the controller is connected to a control end of the analog switch;
• wherein the series circuit is configured to convert a photocurrent outputted by the BOSA into an analog voltage, the different sampling end is configured to sample the analog voltage outputted by the series circuit, the analog switch is configured to output, to the analog-to-digital converter, an analog voltage sampled by a conduction sampling end of the analog switch, and a first sampling end serves as the conduction sampling end to conduct to the output end of the analog switch;
• wherein the analog-to-digital converter is configured to perform analog-to-digital conversion on the analog voltage sampled by the conduction sampling end to generate a digital voltage, and output the digital voltage to the controller;
• and
• wherein the controller is configured to:
• when the digital voltage is greater than or equal to a first preset voltage threshold, output a first control signal to the analog switch, wherein the first control signal triggers 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, and 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 first preset voltage threshold, control a second output end of the controller to output the digital voltage, wherein the first preset voltage threshold falls within a sampling voltage range of the analog-to-digital converter.

A method, comprising:

• receiving, by a controller, a digital voltage outputted by an analog-to-digital converter, wherein an analog-to-digital converter protection circuit comprises an analog switch, the analog-to-digital converter, the controller, and a series circuit, the series circuit comprises a plurality of resistors connected in series, a head end of the series circuit is configured to be connected to an output end of a bi-directional optical sub-assembly (BOSA), a tail end of the series circuit is configured to be grounded, a ground-distant end of each resistor in the series circuit is connected to a different sampling end of the analog switch, an output end of the analog switch is connected to an input end of the analog-to-digital converter, an output end of the analog-to-digital converter is connected to an input end of the controller, a first output end of the controller is connected to a control end of the analog switch, and wherein the digital voltage is a digital voltage obtained by the analog-to-digital converter by performing analog-to-digital conversion on an analog voltage sampled by a conduction sampling end of the analog switch, and a first sampling end serves as the conduction sampling end to conduct to the output end of the analog switch;
• when the digital voltage is greater than or equal to a first preset voltage threshold, outputting, by the controller, a first control signal to the analog switch, wherein the first control signal triggers 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, an analog voltage sampled by the second sampling end is less than an analog voltage sampled by the first sampling end, and the first preset voltage threshold falls within a sampling voltage range of the analog-to-digital converter;
• and
• when the digital voltage is less than the first preset voltage threshold, controlling, by the controller, a second output end of the controller to output the digital voltage.

A controller of an analog-to-digital converter protection circuit, comprising:

• a processor;
• a memory;
• an input port;
• a first output port;
• and
• a second output port;
• wherein the analog-to-digital converter protection circuit comprises an analog switch, an analog-to-digital converter, the controller, and a series circuit, the series circuit comprises at least two resistors connected in series, a head end of the series circuit is configured to be connected to an output end of a bi-directional optical sub-assembly (BOSA), a tail end of the series circuit is configured to be grounded, a ground-distant end of each resistor in the series circuit is connected to a different sampling end of the analog switch, an output end of the analog switch is connected to an input end of the analog-to-digital converter, an output end of the analog-to-digital converter is connected to the input port, and the first output port is connected to a control end of the analog switch;
• wherein the input port is configured to receive a digital voltage outputted by the analog- to-digital converter, wherein the digital voltage is a digital voltage obtained by the analog-to- digital converter by performing analog-to-digital conversion on an analog voltage sampled by a conduction sampling end of the analog switch, and a first sampling end serves as the conduction sampling end to conduct to the output end of the analog switch;
• wherein the memory stores a set of program code, and the processor is configured to invoke the program code stored in the memory to determine whether the digital voltage is greater than or equal to a first preset voltage threshold, wherein the first preset voltage threshold falls within a sampling voltage range of the analog-to-digital converter;
• wherein the first output port is configured to, when the digital voltage is greater than or equal to the first preset voltage threshold, output a first control signal to the analog switch, wherein the first control signal is used 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, and an analog voltage sampled by the second sampling end is less than an analog voltage sampled by the first sampling end;
• and
• wherein the second output port is configured to, when the digital voltage is less than the first preset voltage threshold, output the digital voltage.