System and method for determining a primary switching event in an isolated converter

Abstract

Disclosed is a system for determining a primary switching event in an isolated converter having a primary-side and a secondary-side. The system includes a primary-switch (PS) on the primary-side, a synchronous rectifier (SR) on the secondary-side, an integration circuit, and a SR controller. The integration circuit is in signal communication with the SR on the secondary-side and the SR controller is in signal communication with the SR and the integration circuit. The SR is configured to produce a drain-to-source voltage (VDS) and the integration circuit is configured to integrating a difference between the VDS and a output voltage (VOut) (produced by the secondary-side) over time to produce a VDS over time value (VTime). The SR controller is configured to determine if the VDS is greater than a first threshold voltage (VTH) and determine the primary switching event when the VTime is greater than a second threshold voltage (VSTH).

Dependencies are inferred from the claim text.