Method and apparatus for multiple output regulation in a step-down switching regulator
US5532577A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 1, 1994 |
| Grant date | Jul 2, 1996 |
| Priority date | — |
| Expiry date | Apr 1, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M1/009
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A step-down switching regulator of the present invention includes (1) a magnetic storage device having at least one primary output and one secondary output, (2) a current sensing device for detecting current through a primary winding of the magnetic storage device, (3) a first switch, (4) a second switch, (5) a first comparator for detecting whether the current through the primary winding is greater than a limit value, (6) a second comparator for detecting loss of regulation in the secondary output, and (7) a switch logic circuitry for allowing only one of the first switch or the second switch to turn on at a time. When the primary output is out of regulation, the first switch turns on to deliver power to the primary output. When the secondary output is out of regulation, one of two methods can be used to supply power to the secondary output. A first method turns on the first switch for a short time, and then the second switch turns on to deliver power to the secondary output. A second method turns on the second switch without first turning on the first switch. In either methods, the second switch can be turned off at the end of a pre-determined time period, at the end of a clock c…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.