Automatic bandwidth and stability control for switched pulse width modulation voltage regulator
US6583609B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | May 1, 2002 |
| Grant date | Jun 24, 2003 |
| Priority date | — |
| Expiry date | May 1, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M3/156
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
One aspect of the present invention detects an equivalent series resistance (ESR) of an external capacitor and adjusts a transfer function of a feedback loop of the voltage regulator to compensate for the ESR. The ESR is detected by measuring a phase shift in a ripple voltage signal of an output voltage of the voltage regulator. Based upon the measured phase shift, an adjustable capacitance is introduced to the feedback loop to compensate for the ESR by introducing a zero to the transfer function to stabilize the voltage regulator circuit. Another aspect of the present invention is to adjust the transfer function of the feedback loop to improve transient response. By measuring both the phase shift and the amplitude of the ripple voltage signal, a gain and the position of a pole in the transfer function of the feedback loop may be adjusted to improve the transient response.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.