Current limit protection scheme for PWM buck converter with synchronous rectifier
US6970339B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 27, 2004 |
| Grant date | Nov 29, 2005 |
| Priority date | — |
| Expiry date | Apr 27, 2024 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B70/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A embedded overcurrent protection circuit within the PWM feedback controller (30) of a power converter (100) having an novel current limit detection function that minimizes the effects of the turn-on period of the power device (14) is disclosed herein. This power converter includes a current limit detection circuit (10–20) that is reset on the rising edge of the system clock in a first step. In a second step, the power device (14) that is turned on. In another step, a current detecting circuit (10–20) detects the drain-to-source voltage across the power device (14) and the output current generated thereby. A sense circuit (18) compares the output current detected with a first predetermined limit value in another step. When the output current is less than the first predetermined limit value, a step is conducted where the output current is regulated by modulating the pulse width of the signal sent by a driver (12) to the control node of the power device (14). In the alternative, when the output current exceeds the first predetermined limit value, the power device (14) is turned off and the synchronous rectifier (16) is turned on while its current is monitored at a second predetermine…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.