Reactive networks to reduce acoustic noise and ensure maximum efficiencies in driving piezoelectric elements in haptic applications
US8305200B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 2, 2009 |
| Grant date | Nov 6, 2012 |
| Priority date | — |
| Expiry date | May 30, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/351
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A device and method are provided to drive piezoelectric elements in haptic applications. In one embodiment, a pattern generator provides user programmable PWM waveforms to a driver. The load of the driver is an inductor in series with the piezoelectric element. The filtration of the inductor in series with the capacitance of the piezoelectric element suppresses the high-frequency components of the PWM pulse train, and recovers a value commensurate with the duty cycle of the PWM pulse train. The resulting waveform across the piezoelectric element is converted to physical motion, thereby creating a haptic effect on a user interface. Advantageously, there is reduced power loss, reduced switching induced noise, and a more haptic rich environment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.