Driving voltage output circuit

1 . A driving voltage output circuit for selectively outputting a positive driving voltage and a negative driving voltage, comprising:

an amplifier which amplifies and outputs, as a driving voltage, a selectively input positive or negative input signal; and

a power supply voltage switching circuit which switches a power supply voltage to be supplied to the amplifier according to a polarity of the input signal.

2 . The driving voltage output circuit of claim 1 ,

wherein a state of the amplifier is switched selectively between a current source state and a current sink state according to the polarity of the input signal.

3 . The driving voltage output circuit of claim 1 ,

wherein a potential of an input terminal of the amplifier is grounded prior to reversion of a polarity of the driving voltage.

4 . The driving voltage output circuit of claim 3 , further comprising:

an input selector which inputs to the amplifier a positive polarity input signal source or a negative polarity input signal source selectively, the input selector including:

first and second positive polarity switches provided in series between the positive polarity input signal source and the amplifier;

first and second negative polarity switches provided in series between the negative polarity input signal source and the amplifier; and

ground switches connected between a ground and a connecting line between the first and second positive polarity switches and between the ground and a connecting line between the first and second positive polarity switches.

5 . The driving voltage output circuit of claim 1 ,

wherein the amplifier includes first and second amplifiers which output driving voltages of which polarities are reverse to each other, and

a distributing circuit is provided which outputs the driving voltages output from the first and second amplifiers sequentially and selectively to a plurality of driven electrodes, the distributing circuit outputting the driving voltages output from the first and second amplifiers to at least every other driven electrode.

6 . The driving voltage output circuit of claim 1 ,

wherein the amplifier includes first and second amplifiers which output driving voltages of which polarities are reverse to each other,

an output selector is provided which selectively switches a state between a first state and a second state, the first state being a sate where the driving voltage output from the first amplifier is output to a first driven electrode while the driving voltage output from the second amplifier is output to a second driven electrode, and the second state being a state where the driving voltage output from the first amplifier is output to the second driven electrode while the driving voltage output from the second amplifier is output to the first driven electrode, and

potentials of the first and second driven electrodes are grounded prior to state switch between the first state and the second state.

7 . The driving voltage output circuit of claim 6 ,

wherein the output selector includes:

pairs of first switches and second switches respectively provided in series between the first amplifier and the first driven electrode, between the first amplifier and the second driven electrode, between the second amplifier and the first driven electrode, and between the second amplifier and the second driven electrode; and

grounding switches connected between the ground and the connecting lines between the respective pairs of the first and second switches.