Switch circuit with bidirectional current sensing

A switch circuit, comprising:

• a first switch and a second switch, coupled between a first terminal and a second terminal of the switch circuit, and configured to control a conductive state between the first terminal and the second terminal according to a control signal;
• and
• a current sensing circuit, configured to sense a first switch current flowing through the first switch;
• wherein the current sensing circuit includes:
• a third switch, configured such that a gate and a source of the third switch are coupled in parallel with the first switch, to generate a third switch current;
• a first error amplifier circuit, configured to control a drain voltage of the third switch to track a drain voltage of the first switch through feedback control, such that the third switch current is positively correlated with the first switch current;
• and
• a current-to-voltage conversion circuit, configured to generate a sensing voltage based on the third switch current, wherein the sensing voltage is positively correlated with the first switch current.