Apparatus and method for projected on-time regulator
US7671573B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 29, 2008 |
| Grant date | Mar 2, 2010 |
| Priority date | — |
| Expiry date | Sep 18, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M3/156
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A projected on-time (POT) switching regulator is provided. The regulator includes a switching regulator controller and a main switch. The controller includes a feedback comparator and an on-timer. The feedback comparator compares the output voltage to a reference voltage. Whenever the feedback comparator trips, the main switch is turned on, and the on-timer controls the turn-on duration (on-time) of the main switch, where the duration is adjusted by the input and output voltages according to a preset transfer function. The transfer function is applicable to both CCM and DCM operation. However, during CCM mode operation, at least above a minimum on-time, the on-time is adjusted so that the switching frequency of the regulator is approximately constant. The on-timer includes a comparator that compares an adjustable voltage VFQ to a ramp voltage VIFQ generated by providing an adjustable current IFQ to a capacitor CREF. VFQ and IFQ are adjusted so that, during CCM mode operation, at least above the minimum on-time, the switching frequency of the regulator is approximately constant.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.