Patent · US Active

Switch mode power supply controller with feedback signal decay sensing

US8446746B2 · kind B2 · utility

7Cited by
35References
35Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 1, 2010
Grant dateMay 21, 2013
Priority date
Expiry dateSep 12, 2031

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02M3/33523
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

This invention relates to SMPS controllers employing primary side sensing. We describe a system for identifying a knee point in a sensing waveform, at which the output voltage of the SMPS may be sampled accurately on the primary side. The system identifies the knee point, broadly speaking, by tracking a portion of a power transformer voltage waveform, and samples the voltage waveform at the knee point to determine the SMPS output voltage. In preferred embodiments this technique is implemented using a circuit akin to a decaying peak detector, providing a timing signal indicating detection of the knee point. Sample/hold and error amplifier circuits may be employed to achieve output voltage regulation.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.