Synchronizing a switched power supply
US9304625B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2013 |
| Grant date | Apr 5, 2016 |
| Priority date | — |
| Expiry date | Nov 10, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M3/156
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Embodiments described herein synchronize a switching frequency of switched power supplies with timing events associated with updating a display screen or performing touch sensing. For example, a touch event may be the time needed for a touch controller to scan a plurality of sensing electrodes. Because noise is introduced each time switched power supplies switch between different stages, the touch controller may instruct a power management controller to switch between the stages (i.e., adjust the switching frequency) at the same time during each touch event. Even though the switched power supplies are permitted to introduce noise into the touch system, the noise happens at the same time during each touch event. Accordingly, the effect of the noise is the same for each touch event and is cancelled out. A similar process may be used for synchronizing the switching frequency to display events.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.