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A driver amplifier circuit is provided which includes a voltage level shifting circuit and an Op-Amp. A positive power supply terminal and a negative power supply terminal of the Op-Amp receive a first reference voltage and a second reference voltage outputted from the voltage level shifting circuit

A driver amplifier circuit is provided which includes a voltage level shifting circuit and an Op-Amp. A positive power supply terminal and a negative power supply terminal of the Op-Amp receive a first reference voltage and a second reference voltage outputted from the voltage level shifting circuit, causing a DC voltage level of an output signal to be equal to 0V. Meanwhile, the absolute value of a voltage difference between the first reference voltage and the second reference voltage is equal to VDD, meaning that elements in the circuit operate without risking a high-voltage damage.

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What is claimed is: 1. A method for driving an output signal and reducing a DC bias of the output signal, comprising: receiving a first operating voltage having a magnitude with reference to ground; performing a level shifting of the first operating voltage to generate a second operating voltage, w

What is claimed is: 1. A method for driving an output signal and reducing a DC bias of the output signal, comprising: receiving a first operating voltage having a magnitude with reference to ground; performing a level shifting of the first operating voltage to generate a second operating voltage, wherein the second operating voltage is defined by positive and negative values with reference to ground, wherein the total magnitude between the positive and negative values is less than twice that of the magnitude of the first operating voltage; providing the second operating voltage to an amplifier such that the amplifier is substantially biased at zero voltage; and driving an input signal by the amplifier to generate an output signal. 2. The method of claim 1, wherein the magnitude of each of the positive and negative values of the second operating voltage with reference to around is substantially equal to half that of the first operating voltage with reference to ground. 3. The method of claim 2, wherein the first operating voltage comprises a first voltage and a second voltage GND, and the second operating voltage comprises a third voltage and a fourth voltage. 4. The method of claim 1, wherein the generation of the second operating voltage comprises: generating the positive value of the second operating voltage; and generating the negative value of the second operating voltage; wherein a mean of the positive voltage and the negative voltage is substantially equal to zero. 5. The method of claim 4, wherein the negative value is generated by a charge pump. 6. A driver amplifier comprising: a voltage level shifting circuit comprising a plurality of switches and capacitors configured to receive a first operating voltage and output a second operating voltage, wherein the second operating voltage is defined by positive and negative values with reference to ground, wherein the total magnitude between the positive and negative values is less than twice that of the first operating voltage with reference to ground; and a driver circuit having first and second power leads which are coupled to the second operating voltage such that the driver circuit is substantially biased at zero voltage, the driver circuit receiving an input signal to drive an output signal, wherein the DC component of the output signal is substantially equal to zero. 7. The circuit of claim 6, wherein the magnitude of each of the positive and negative value of the second operating voltage with reference to ground is substantially equal to half that of the first operating voltage with reference to ground. 8. The circuit of claim 7, wherein the voltage level shifting circuit shifts the first operating voltage to output the second operating voltage. 9. The circuit of claim 6, wherein the magnitude of the first operating voltage is substantially equivalent to that of the second operating voltage. 10. The circuit of claim 9, wherein the first operating voltage comprises a first voltage and a second voltage GND, and the second operating voltage comprises a third voltage and a fourth voltage. 11. The circuit of claim 10, wherein the voltage level shifting circuit comprises: a pair of first switches, a pair of first terminals of the pair of first switches respectively receiving the first voltage and the second voltage GND; a pair of second switches, a pair of first terminals of the pair of second switches coupled with a pair of second terminals of the pair of first switches; a first capacitor, two terminals of the first capacitor respectively coupled to the pair of the second terminals of the pair of first switches; and a second capacitor, two terminals of the second capacitor are respectively coupled to the pair of the second terminals of the pair of second switches for outputting the third voltage and the fourth voltage. 12. The circuit of claim 9, wherein the voltage level shifting circuit comprises a charge pump. 13. The circuit of claim 6, wherein the voltage level shifting circuit comprises: a positive power generator for receiving the first operating voltage and outputting the positive value of the second operating voltage; and a negative power generator for receiving the first operating voltage and outputting the negative value of the second operating voltage; wherein a mean of the positive value and the negative value is substantially equal to zero. 14. The circuit of claim 13, wherein the negative power generator comprises a charge pump. 15. The circuit of claim 14, wherein the negative power generator further comprises: a voltage detector for detecting the negative voltage and outputting a control signal; and an oscillating signal generator for outputting an oscillating signal according to the control signal, wherein the oscillating signal is used to control operations of the charge pump. 16. The circuit of claim 15, wherein the voltage detector comprises: a comparator for comparing a comparing voltage with a reference voltage to generate a compared signal, wherein the comparing voltage corresponds to the negative voltage; and a pulse width generator for outputting the control signal according to the compared signal. 17. The circuit of claim 6, wherein the voltage generator comprises a charge pump. 18. The circuit of claim 17, wherein the charge pump comprises a pair of first switches, a pair of second switches, a first capacitor, and a second capacitor. 19. The circuit of claim 18, wherein the first and the second capacitors have capacitances within the range of several microfarads (μF) and switching frequencies of the first switches and the second switches are in the range of several hundreds of KHz. 20. The circuit of claim 6, wherein the driver circuit comprises at least one element configured to withstand a maximum voltage of less than twice the magnitude of the first operating voltage with reference to ground.