Abstract:
A method of driving a lamp that uses a DC to AC inverter that is connected to a primary winding of a transformer is disclosed. The inverter frequency is variable, and in one embodiment, may be controlled by a voltage controlled oscillator. Circuitry is included that monitors the phase relationship between a voltage across a secondary of the transformer and a current through the primary of the transformer. The circuitry monitors the phase relationship and adjusts the inverter frequency, such as by adjusting voltage controlled oscillator, so that the phase relationship is maintained at a predetermined relationship.
Abstract:
A technique for driving one or more EEFLs, having first and second ends, in a bank of EEFLs involves driving the EEFLs at both the first and second ends. In a non-limiting embodiment, a device constructed according to the technique may include a bank of EEFLs connected in parallel. The device may further include a first transformer, wherein a first of the secondary windings of the first transformer is coupled to the first end of the bank of EEFLs. The device may further include a second transformer, wherein a first of the secondary windings of the second transformer is coupled to the second end of the bank of EEFLs.
Abstract:
The described DC to AC inverter efficiently controls the amount of electrical power used to drive a cold cathode fluorescent lamp (CCFL). Additionally, during striking of the CCFL, a higher energy initial energy pulse is used. During normal operation, a lower energy pulse is used.
Abstract:
A method of driving a lamp that uses a DC to AC inverter that is connected to a primary winding of a transformer is disclosed. The inverter frequency is variable, and in one embodiment, may be controlled by a voltage controlled oscillator. Circuitry is included that monitors the phase relationship between a voltage across a secondary of the transformer and a current through the primary of the transformer. The circuitry monitors the phase relationship and adjusts the inverter frequency, such as by adjusting voltage controlled oscillator, so that the phase relationship is maintained at a predetermined relationship.