Retrofit lamps and lighting systems that use retrofit lamps

摘要

Retrofit lamps are used with ballasts. A shunt switch is provided in parallel with the output load and is adapted to shunt the input terminals of the lamp using pulse width control to regulate the current through the illumination element. This current control is used to allow compatibility with various ballasts and to provide dimming control. A detection circuit is used to detect anomalous driving conditions in the retrofit lamp, and the pulse width control of the shunt switch is then overridden by keeping the shunt switch in a stable state for a certain duration. be able to. This prevents overload conditions and avoids DC signals in the event of component failure.