Semiconductor device and display device

A display device comprising:

• a display panel;
• a driver circuit configured to drive the display panel;
• a microprocessor configured to distinguish still image data and moving image data contained in electronic data to be displayed by the display panel;
• and
• a DC-DC converter circuit electrically connected to the driver circuit and to an output of the microprocessor, the DC-DC converter circuit comprising:
• a conversion circuit;
• a comparison circuit comprising an input terminal electrically connected to an output terminal of the conversion circuit, the output terminal being configured to output an output voltage of the DC-DC converter circuit;
• and
• a logic circuit configured to perform an arithmetic operation and comprising a first input terminal electrically connected to an output terminal of the comparison circuit and a second input terminal, the logic circuit being an AND circuit,
• wherein an output terminal of the logic circuit is electrically connectable to an input terminal of the conversion circuit,
• wherein the microprocessor is configured to output a clock signal to the second input terminal of the logic circuit,
• wherein the display panel is configured to be driven in accordance with an output voltage of the DC-DC converter circuit,
• wherein the display panel is configured to control the DC-DC converter circuit to perform a hysteresis control when still image data are to be displayed and a pulse width modulation control when moving image data are to be displayed, and
• wherein the display device is configured to connect the output terminal of the logic circuit to the input terminal of the conversion circuit when performing the hysteresis control.

A semiconductor device comprising:

• a display panel;
• a driver circuit configured to drive the display panel, and
• a DC-DC converter circuit, the DC-DC converter circuit comprising:
• a conversion circuit comprising:
• an inductor;
• and
• a transistor comprising a drain terminal and a source terminal, one of which is connected to the inductor;
• an amplification circuit electrically connected to an output terminal of the conversion circuit;
• a first multiplexer comprising a first input terminal electrically connected to the output terminal of the conversion circuit so that a voltage applied to the first input terminal can be proportional to a voltage of the output terminal of the conversion circuit, and a second input terminal electrically connected to an output terminal of the amplification circuit;
• a comparison circuit comprising an input terminal electrically connected to an output terminal of the first multiplexer;
• a logic circuit configured to perform an arithmetic operation and comprising a first input terminal electrically connected to an output terminal of the comparison circuit and a second input terminal, the logic circuit being an AND circuit;
• and
• a second multiplexer comprising a first input terminal electrically connected to an output terminal of the logic circuit, a second input terminal electrically connected to an output terminal of the comparison circuit, and an output terminal electrically connected to a gate of the transistor, and
• a microprocessor configured to output a clock signal to the second input terminal of the logic circuit,
• wherein a current output by the logic circuit can be input to the gate of the transistor via the second multiplexer,
• wherein the microprocessor is configured to distinguish still image data and moving image data contained in electronic data to be displayed by the display panel, and
• wherein the display panel is configured to control the DC-DC converter circuit to perform a hysteresis control when still image data are to be displayed and a pulse width modulation control when moving image data are to be displayed.