Short-circuit protection circuit for voltage sampling resistor of primary side converter
US9923365B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 18, 2016 |
| Grant date | Mar 20, 2018 |
| Priority date | — |
| Expiry date | Nov 19, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M1/36
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Disclosed is a short-circuit protection circuit for a voltage sampling resistor of a primary side converter, comprising a high voltage power transistor, a high voltage starting resistor, a first voltage dividing resistor of a port VDD, a second voltage dividing resistor of the port VDD, an NMOS transistor, a diode, a first comparator, a second comparator, a third comparator, a time delay circuit, a filter, a first logic circuit, a second logic circuit, a current supply, a first AND gate and a first inverter. The chip of the present disclosure is capable of correctly and effectively detecting whether the sampling resistor is shorted or not before the chip works normally, thereby avoiding the risk of damaging the chip by large current from the voltage feedback port FB due to turn-on of the switching transistor when the upper voltage sampling resistor is shorted, and greatly reducing the input power.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.