Calibration techniques for alternating-current (AC)-coupled transceiver

A system comprising:

• a first device comprising a capacitor coupled to a first side of a channel and a transmitter coupled to the capacitor;
• a second device comprising a receiver having a transimpedance amplifier coupled to an input node, wherein the input node is to be coupled to a second side of the channel;
• and
• calibration circuitry coupled between the input node and the capacitor, the calibration circuitry to:
• modify a capacitance of the capacitor based on each of a plurality of control values;
• generate, for each control value, a first digital code for a direct current (DC) swing and a second digital code for an alternating current (AC) swing at the input node;
• and
• determine a final control value of the plurality of control values that minimizes a difference between the first and second digital codes.

A circuit comprising:

• a receiver to be coupled to a channel, which is coupled to a transmitter, wherein the receiver comprises:
• at least one capacitor coupled between the channel and a ground;
• and
• a transimpedance amplifier coupled to an input node coupled to the channel;
• and
• calibration circuitry coupled between the input node and the at least one capacitor, the calibration circuitry to:
• modify a capacitance of the at least one capacitor based on each of a plurality of control values;
• generate, for each control value, a first digital code for a direct current (DC) swing and a second digital code for an alternating current (AC) swing at the input node;
• and
• determine a final control value of the plurality of control values that minimizes a difference between the first and second digital codes.