Dual PWM relay driver with diagnostics for functional safety system
US11114842B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 27, 2020 |
| Grant date | Sep 7, 2021 |
| Priority date | — |
| Expiry date | May 27, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/3278
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A component includes first and second switches in series and connected between a power source and a coil of contacts of a safety relay. A first controller controls the first switch with a close signal that closes the first switch or a first PWM signal that opens and closes the first switch on each PWM cycle. A second controller controls the second switch with a close signal that closes the second switch or a second PWM signal that opens and closes the second switch on each PWM cycle. A PWM sensing circuit connected to the coil sends a sensed PWM signal to an input of the first and second controllers. The first controller sends the first PWM signal while the second controller sends a close signal and vice-versa. The controllers verify that the received PWM signal matches the sent PWM signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.