Accurate feed-forward sensing in flyback-transformer based secondary controller
US10693384B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 23, 2019 |
| Grant date | Jun 23, 2020 |
| Priority date | — |
| Expiry date | Sep 23, 2039 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B70/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A secondary side controller for an AC-DC converter and method for operating the same are provided. Generally, the controller includes a single synchronous rectifier sense (SR-SNS) pin coupled to a drain of a SR on a secondary of a transformer to sense a voltage (VSRD). In feed-forward (FF) mode VSRD is a sum of a voltage (VIN) on a primary divided by a turn-ratio (N) of the transformer and an output bus voltage (VBUS). A voltage-to-current (V2I) converter coupled to the SR-SNS pin and to the output bus removes VBUS from VSRD. A sample and hold (S/H) module coupled to the SR-SNS pin samples a voltage (VSAMP) including information on VIN/N. A VIN/N V2I converter coupled to the S/H module converts VSAMP to a feed-forward current (IFF), and a cancellation and signal module coupled thereto extracts information on VIN from IFF and generates signals to control the AC-DC converter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.