Method and apparatus for generating piezoelectric transducer excitation waveforms using a boost converter
US8854319B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 7, 2011 |
| Grant date | Oct 7, 2014 |
| Priority date | — |
| Expiry date | Apr 18, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M3/33507
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Transducers formed as part of a touchscreen system emulate the motion of a pushbutton or other mechanical elements. A touchscreen system positions a transducer adjacent to an icon displayed on the touchscreen surface. When a user touches the icon, the transducer senses the touch and is then deformed in a pattern that emulates a mechanical motion, giving the user the sensation of touching a mechanical button. An excitation signal applied to the transducer is compared to a target excitation signal that, when applied to the transducer, causes the transducer to emulate the desired motion. When any differences between the two signals are detected, the excitation signal is adjusted so that the motion is corrected. The target excitation signal, or time and voltage segments defining it, are stored in memory and retrieved for comparison. The excitation signal is also selected to reduce any acoustic artifacts that can cause the transducer to generate audible clicks.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.