Overcurrent protection for class D power amplifier

摘要

In an aspect of the disclosure, a class D power amplifier with an overcurrent protection (OCP) circuit is provided. The class D power amplifier includes a plurality of output transistors, and the OCP circuit is mirrored to at least one output transistor of the plurality of output transistors in a closed-loop feedback configuration for precisely controlling a sensing current of the OCP circuit with respect to an output current of the at least one output transistor. The class D power amplifier with the OCP circuit in the closed-loop feedback configuration mitigates a variation in a current threshold value for triggering interruption of the class D power amplifier.

主权项

1. A class D power amplifier with an overcurrent protection (OCP) circuit, comprising:
a class D power amplifier having a plurality of output transistors; and an OCP circuit mirroring at least one output transistor of the plurality of output transistors in a closed-loop feedback configuration for controlling a sensing current of the OCP circuit with respect to an output current of the at least one output transistor, wherein the OCP circuit interrupts operation of the class D power amplifier when the sensing current exceeds a threshold, wherein the threshold varies according to at least one of:
a process for fabricating the OCP circuit and the class D power amplifier,a supply voltage at which the OCP circuit and the class D power amplifier are operated, ora mismatch between the OCP circuit and the class D power amplifier.