Electronic ballast circuit for lamps
AssigneeGenesys Global, LLC
InventorSteve McNay
Life of this patent
Estimating the term…
Abstract
An electronic ballast circuit includes a power factor correction circuit, a control and amplifier circuit, a ballast controller circuit and a ballast driver circuit. The ballast driver circuit includes a resonant circuit that connects to a lamp and a strike voltage limiter circuit that regulates the behavior of the resonant circuit. An overcurrent sensor circuit may be included to indirectly the control the ballast controller circuit via the control and amplifier circuit. The strike voltage limiter circuit uses varistors to change the resonant frequency of the resonant circuit to limit the voltage to the lamp.
Claims20
An electronic ballast circuit for limiting lamp strike voltage, comprising:
- a ballast driver circuit (140) comprising:
- a resonant circuit (620) comprising a first inductor (622), a run capacitor (624) and a strike capacitor (626) connected together in series, the resonant circuit being driven at one end by a resonant circuit drive signal (650) and connected at a second end to a common voltage (CBUS);
- a first lamp lead (144a) connected between the run capacitor (624) and the strike capacitor (626), and a second lamp lead (144b) connected to the common voltage (CBUS);
- and
- a voltage limiter circuit (610) having a first pair of leads connected across the run capacitor (624), and a second pair of leads connected to the common voltage (CBUS).
Dependencies are inferred from the claim text.