Drive circuit for display apparatus and display apparatus
View Patent ↗A drive circuit that is an example of the present invention is a drive circuit of a display device for outputting in parallel the analog picture signals generated based on the digital picture signals inputted in serial. This circuit comprises a level shift circuit for converting the voltage level of the digital picture signals that were inputted in serial, a D/A conversion circuit for generating analog picture signals based on the digital picture signals that were subjected to level conversion with the level shift circuit, and an expansion circuit connected to the output side of the D/A conversion circuit or between the level shift circuit and the D/A conversion circuit and serving to expand and hold the inputted serial picture signals in parallel and output the picture signals in parallel. The level shift circuit is thus formed in the front stage of the picture signal register circuit.
1. A drive circuit for a display apparatus outputting a positive polarity analog picture signal and a negative polarity analog picture signal with respect to a reference voltage to a data line of the display apparatus, comprising:
a positive polarity drive circuit outputting the positive polarity analog picture signal;
a negative polarity drive circuit outputting the negative polarity analog picture signal;
a switching circuit switching the positive polarity analog picture signal and the negative polarity analog picture signal to provide to the data line;
a positive polarity pre-charge switch, formed between the positive polarity drive circuit and the switching circuit, capable of pre-charging the data line to a positive polarity pre-charge voltage before an analog signal provided to the data line is changed from the positive polarity to the negative polarity; and
a negative polarity pre-charge switch, formed between the negative polarity drive circuit and the switching circuit, capable of pre-charging the data line to a negative polarity pre-charge voltage before an analog signal provided to the data line is changed from the negative polarity to the positive polarity.
2. The drive circuit of claim 1 , wherein the reference voltage is system ground voltage.
3. The drive circuit of claim 1 , wherein both the positive polarity pre-charge voltage and the negative polarity pre-charge voltage are system ground voltage.