ANSI reference ballast compliance circuit for LED retrofit lamps
US9468060B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 4, 2015 |
| Grant date | Oct 11, 2016 |
| Priority date | — |
| Expiry date | Mar 4, 2035 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An embodiment of the present invention provides a retrofit LED lamp that is operated by a dual mode circuit, enabling maximum compatibility with the ANSI reference ballasts to satisfy UL requirements to replace HID and fluorescent lamps. The LED lamp operates at two different modes, offered by the dual mode PCB circuit. In one of the mode, namely ANSI ballast testing, a low frequency current from the ballast is throttled through a bypass circuit to LEDs, since a field effect transistor of the circuit is in open circuit mode due to insufficient current. During the second mode, namely field ballast operation, a high frequency current is provided by the ballast, which short circuits the FET, causing it to conduct and thus operating the LEDs. Advantageously, the LED lamp offers maximum compatibility with ballasts using such dual mode circuit and consumes less power.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.