Patent ID: 7242153
Filing Date: 2007-07-10
Classification: G09G,H05B,Y10S

Abstract:
1. An inverter circuit, comprising: a direct current (DC) power source; a power switch driver, the power switch driver outputting a pulse width modulation signal according to a voltage of the DC power source; a power switch, comprising a first terminal, a second terminal, and a third terminal, the first terminal of the power switch electrically coupled to the DC power source, the second terminal of the power switch receiving the pulse width modulation signal, the third terminal of the power switch determining whether to output a signal used to transfer the power from the DC power source according to the pulse width modulation signal; a transformer unit, comprising an input terminal and an output terminal, the input terminal of the transformer receiving the signal used to transfer the power from the DC power source, the output terminal of the transformer outputting an alternating current(AC) signal; a load, comprising an input terminal and an output terminal, the input terminal of the load receiving the AC signal, and letting the AC signal flow from the input terminal of the load to the output terminal of the load; a detecting unit, the detecting unit outputting a feedback control signal to regulate the AC signal flowing through the load, and a load turn-on signal which indicates a turn-on situation of the load; an oscillator, receiving the feedback control signal, and outputting an oscillation signal according to the feedback control signal, the feedback control signal determining a frequency of the oscillation signal, the oscillation signal being transmitted to the power switch driver to determine a frequency of the pulse width modulation signal outputted from the power switch driver; a system trigger apparatus, setting the feedback control signal as a predetermined value every time the system trigger apparatus of the inverter circuit is turned on so that the oscillator outputs an oscillation signal with a predetermined frequency; and a protection apparatus, determining whether to change the pulse width modulation signal according to the load turn-on signal.