POWER SUPPLY APPARATUS, LIQUID CRYSTAL DRIVING APPARATUS AND DISPLAY APPARATUS

摘要

A power supply apparatus comprises a constant voltage generating part (first DAC (21), second DAC (22), resistor (R2), resistor (R3)) that generates a constant voltage (Va) of positive polarity; a pulse voltage generating part (pulse oscillator (23), amplifier (24)) that generates a pulse voltage (Vb) of positive polarity; a capacitor (C1) an end of which is connected to the output terminal of the pulse voltage generating part; and a diode (D1) the anode of which is connected to the other end of the capacitor (C1) and the cathode of which is connected to the output terminal of the constant voltage generating part. A pulse voltage (Vc) having the positive and negative polarities is outputted from the other end of the capacitor (C1). In this way, a simple and small-scale circuit arrangement can be used to generate a pulse voltage having the positive and negative polarities.