Device and method for detecting an average output current of a power converter

摘要

A device for detecting an average output current of a power converter includes a current generation unit, a first voltage generation unit, a first current mirror unit, and a second current mirror unit. The current generation unit generates a first charge current according to an intermediate voltage. The first voltage generation unit generates a first node voltage according to the first charge current, a first discharge current, a turning-on time, and an inverse turning-on time. The first current mirror unit generates a first current according to the first node voltage, and generates a second voltage corresponding to the average output current of a secondary side of the power converter according to the first current. The second current mirror unit generates the first discharge current according to the first current.

主权项

1. A controller for detecting an output current of a power converter, the controller comprising:
a comparison unit for generating a first variable turning-on time according to a detection voltage, an intermediate voltage, and a turning-on time of a power switch of a primary side of the power converter, wherein a second variable turning-on time is equal to the turning-on time minus the first variable turning-on time; and an intermediate voltage generation unit coupled to the comparison unit, a charge current, and a discharge current for adjusting the intermediate voltage according to the first variable turning-on time, the second variable turning-on time, the turning-on time, the charge current, and the discharge current, wherein the output current corresponds to the intermediate voltage.