Output drive circuit, signal conversion method and parallel-to-serial transmitter

The present invention relates to a low to high voltage conversion output driver circuit. The low to high voltage conversion output driver has an output coupled to a first fixed voltage via a load device and comprises a current source, a low voltage transistor, and a high voltage transistor. The current source has one end coupled to a second fixed voltage. The low voltage transistor has a first terminal coupled to the other end of the current source, a second terminal receiving a low voltage data signal, and a third terminal. The high voltage transistor has a first terminal coupled to the third terminal of the low voltage transistor, a second terminal coupled to a bias source, and a third terminal coupled to the output. Wherein, the output is used for outputting high voltage data signals, and any two end of the high voltage transistor is able to bear higher voltage with respect to the low voltage transistor. The low to high voltage conversion output driver circuit provided by the invention is capable of converting the low voltage serial data to high voltage without level translator. Thereby, the chip area and the consumption of the level translator can be saved, at the same time, time series jitter generated by the low bandwidth of the level translator is reduced.