DC electronic switch with temperature independent current limit
US11031775B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 11, 2019 |
| Grant date | Jun 8, 2021 |
| Priority date | — |
| Expiry date | Oct 13, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M1/0009
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A negative feedback closed loop circuit composed of an operational amplifier, a main switch, and a current sense resistor is applied to limit the current to a pre-defined threshold whenever there is an overload or short circuit condition is the circuit. A timing circuit composed of resistors and a capacitor is used to provide timing of turning off the circuit. The timing circuit is always charged from the same voltage and started from the same moment of main switching entering into current limit mode. The voltage reference is set by a voltage divider. The timing capacitor voltage and the voltage reference is compared in a comparator. Since both the amplifier circuit and the comparator circuit are temperature independent, the current limiting point and the time delay to turn off the switch are also both independent of temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.