Circuit and method for determining whether AC mains voltage is below or above a predetermined set point
US6208258A · kind A · utility
4Cited by
5References
25Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 30, 1999 |
| Grant date | Mar 27, 2001 |
| Priority date | — |
| Expiry date | Sep 30, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H3/247
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A circuit for detecting whether or not an AC voltage mains is providing an AC voltage above a predetermined point including a full wave bridge and voltage divider, a voltage detection circuit including a pair of transistors and a zener diode, an optical coupler including a light emitting diode (LED) and photo transistor, a comparator circuit for determining whether or not the AC voltage source has been below a predetermined voltage for a predetermined length of time including a comparator circuit such as a comparator or a FET.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.