Driving circuit for electrophoretic display device
AssigneeSemiconductor Components Industries, LLC
InventorToshiyuki Onoue
Life of this patent
Estimating the term…
Abstract
There is offered a driving circuit for an electrophoretic display device directed to avoiding a problem that clearing display on a display unit is not performed when the power supply is lost and a wrong display such as wrong time display is left unchanged. In the driving circuit for the electrophoretic display device, either a display clearing signal or a display retaining signal is set in a display setting register in advance. When the loss of the power supply is detected by a low voltage detection circuit while the display clearing signal is retained in the display setting register, the display on the display unit is cleared or retained in accordance with the setting in the display setting register.
Claims20
A driving circuit for an electrophoretic display device that comprises a common electrode to which a common voltage is applied, a pixel electrode and an electrophoretic particle interposed between the common electrode and the pixel electrode, the driving circuit comprising:
- a first backup capacitor retaining a first voltage that is higher than a power supply voltage;
- a second backup capacitor retaining a second voltage that is higher than the first voltage;
- a third backup capacitor retaining a third voltage that is generated by inverting the second voltage with reference to the common voltage;
- a display setting register retaining either a display clearing signal or a display retaining signal;
- a low voltage detection circuit detecting a reduction in the power supply voltage;
- a display setting circuit outputting the display clearing signal when the low voltage detection circuit detects the reduction in the power supply voltage while the display setting register retains the display clearing signal;
- and
- a drive voltage output circuit outputting the second voltage, the third voltage or the common voltage to the pixel electrode in accordance with display data, the drive voltage output circuit being configured to output the second voltage or the third voltage to the pixel electrode in accordance with the display clearing signal.
A driving circuit for an electrophoretic display device that comprises a common electrode to which a common voltage is applied, a pixel electrode and an electrophoretic particle interposed between the common electrode and the pixel electrode, the driving circuit comprising:
- a first backup capacitor retaining a first voltage that is higher than a power supply voltage;
- a second backup capacitor retaining a second voltage that is higher than the first voltage;
- a third backup capacitor retaining a third voltage that is generated by inverting the second voltage with reference to the common voltage;
- a display setting register retaining either a display clearing signal or a display retaining signal;
- a low voltage detection circuit detecting a reduction in the power supply voltage, the low voltage detection circuit being supplied with the first voltage;
- a display setting circuit outputting the display clearing signal when the low voltage detection circuit detects the reduction in the power supply voltage while the display setting register retains the display clearing signal, the display setting circuit being supplied with the first voltage;
- and
- a drive voltage output circuit outputting the second voltage, the third voltage or the common voltage to the pixel electrode in accordance with display data, the drive voltage output circuit being configured to output the second voltage or the third voltage to the pixel electrode in accordance with the display clearing signal so that display is cleared.
A driving circuit for an electrophoretic display device comprising:
- a common electrode to which a common voltage is applied;
- a pixel electrode;
- an electrophoretic particle interposed between the common electrode and the pixel electrode;
- a first backup capacitor retaining a first voltage that is higher than a power supply voltage;
- a second backup capacitor retaining a second voltage that is higher than the first voltage;
- a third backup capacitor retaining a third voltage that is generated by inverting the second voltage with reference to the common voltage;
- a low voltage detection circuit detecting a reduction in the power supply voltage;
- a display setting circuit outputting a display clearing signal when the low voltage detection circuit detects the reduction in the power supply voltage;
- and
- a drive voltage output circuit outputting the second voltage, the third voltage or the common voltage to the pixel electrode in accordance with display data, the drive voltage output circuit being configured to output the second voltage or the third voltage to the pixel electrode in accordance with the display clearing signal.
Dependencies are inferred from the claim text.