Protection circuit protecting against voltage irregularities
US6909585B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 9, 2003 |
| Grant date | Jun 21, 2005 |
| Priority date | — |
| Expiry date | Jul 1, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H11/003
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Protection circuits (1) to be located between power supplies (2) and further circuitries (20,30) for protecting further circuitries (20,30) against voltage irregularities and comprising main transistors (7) coupled to switching circuits (10) for rendering main transistors (7) operative/non-operative can be made more allround by providing them with comparators (11) for controlling gate voltages of main transistors (7) via switches (12,13) to get protection against small negative voltage pulses and voltage fluctuations. Said switches (12,13) comprise two switches (12,13) for interrupting a reference voltage generated by a reference voltage source and for supplying a nearby ground voltage to said gate. A diode (14) between switch (13) and gate allows negative voltages at said gate for simplifying the introduction of further stages. Thick oxide transistors (15) protect further circuitries (20,30) and main transistors (7) against large negative voltage pulses. Capacitors (16) and resistors (17) coupled parallelly to thick oxide transistors (15) protect against large negative voltage pulses and reverse polarity. Serial transistors (21) are coupled anti-serially to main transistors (7) to…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.