DISPLAY PANEL AND DISPLAY PANEL DRIVING METHOD

摘要

Display panel includes: a power supply unit that generates first power supply voltage and variable second power supply voltage; and first and second power supply lines that transmit the first and second power supply voltages, respectively, to light emitting elements. The power supply unit (i) includes: first and second input terminals; a switching control unit; an inductor having first terminal connected to the second power supply line; a first switch element that switches conduction/non-conduction between a second terminal of the inductor and the first input terminal; a second switch element that switches conduction/non-conduction between the second terminal and the second input terminal; a capacitor having first electrode to which constant voltage is applied; and a third switch element that switches conduction/non-conduction between the second terminal and a second electrode of the capacitor, and (ii) collects, into the capacitor, and regenerates power from parasitic capacitance of the second power supply line.

主权项

1. A display panel comprising:
a plurality of light-emitting elements; a power supply unit configured to generate, from an input power supply voltage, a first power supply voltage used for light emission by the plurality of light-emitting elements and a second power supply voltage which is variable; a first power supply line that transmits the first power supply voltage from the power supply unit to the plurality of light-emitting elements; and a second power supply line that transmits the second power supply voltage from the power supply unit to the plurality of light-emitting elements, wherein the power supply unit includes:
a pair of input terminals to which the input power supply voltage is applied;a switching control unit;an inductor having a first terminal connected to the second power supply line;a first switch element that is controlled by the switching control unit and switches between a conducting state and a non-conducting state between a second terminal of the inductor and one of the pair of input terminals;a second switch element that is controlled by the switching control unit and switches between the conducting state and the non-conducting state between the second terminal of the inductor and the other of the pair of input terminals;a capacitor having a first electrode to which a constant voltage is applied; anda third switch element that is controlled by the switching control unit and switches between the conducting state and the non-conducting state between the second terminal of the inductor and a second electrode of the capacitor, and the switching control unit is configured to:
place (i) one of the first switch element and the second switch element and (ii) the third switch element in mutually-exclusive states of conduction to accumulate electric charge in the capacitor using current flowing to the inductor, when the second power supply voltage is set to a first voltage; andplace the third switch element in the conducting state to charge a parasitic capacitance of the second power supply line using the electric charge accumulated in the capacitor, when the second power supply voltage is changed from the first voltage to a second voltage.