POWER SOURCE CIRCUIT, DISPLAY DEVICE, AND ELECTRONIC EQUIPMENT

摘要

A power source circuit which can reduce its own power consumption and can select its boosting rate in accordance with the duty ratio. The power source circuit contains a charge pump circuit containing a first switching section (40) which accumulates charges in a capacitor (CP) and a second switching section (42) which transfers the charges accumulated in the capacitor (CP) to another capacitor (CB), and a circuit which generates switching signals for controlling the first and second switching sections. The first switching section (40) contains switching elements (SW11A and SW11B) which are respectively connected to different potentials (VDD and VE1) on one side and to one end of the capacitor (CP) on the other side. The switching signal generating circuit variably controls the boosting rate by turning on or off the switching element (SW11A) and turning off the switching element (SW11B) or by turning on or off the element (SW11B) and turning off the element (SW11A). The potential of the switching signal when the elements (SW11A and SW11B) are turned off is made equal to the potential supplied to the source of a switching transistor. The boosting rate is controlled in accordance with the duty ratio when a liquid crystal display is operated for partial display.