Display driver IC and display apparatus including the same
A display driver integrated circuit (DDI) includes a level shifter unit configured to convert a level of a control signal to a voltage in a range that equal to or greater than a first voltage and is equal to or less than a second voltage and output a switch control signal, and a voltage generator including a capacitor and a switch that is turned on or off based on or in response to the switch control signal and configured to generate at least one third voltage.
1. A display driver integrated circuit (DDI) comprising:
a level shifter unit configured to convert a level of a control signal to a voltage in a range that is equal to or greater than a first voltage and equal to or less than a second voltage and output a switch control signal; and
a voltage generator including a capacitor and a switch that is turned on or off based on or in response to the switch control signal and configured to generate at least one third voltage,
wherein the level shifter unit includes:
a level shifter configured to output a first signal based on or in response to the control signal;
a buffer configured to buffer the first signal and selectively output a second signal to an output node based on or in response to a buffer control signal; and
a pre-charge controller configured to selectively provide a pre-charge voltage to the output node and generate the buffer control signal based on or in response to a pre-charge control signal,
the pre-charge voltage is higher than the first voltage and is lower than the second voltage, and
the output node is connected to the switch.
2. The DDI of claim 1 , wherein the pre-charge controller includes an inverter configured to invert the pre-charge control signal and output the buffer control signal.
3. The DDI of claim 2 , wherein the pre-charge controller includes a positive-polarity control terminal configured to receive the pre-charge control signal, a negative-polarity control terminal configured to receive the buffer control signal, an input terminal configured to receive the pre-charge voltage, and an output terminal connected to the output node.
4. The DDI of claim 1 , wherein the buffer receives the first voltage and the second voltage as bias voltages.
5. The DDI of claim 1 , wherein the first voltage is a negative voltage, the second voltage is a positive voltage, and the pre-charge voltage is a ground voltage.
6. The DDI of claim 1 , wherein when the pre-charge controller provides the pre-charge voltage to the output node, the buffer does not provide the second signal to the output node.
7. The DDI of claim 1 , wherein, when the pre-charge controller blocks the pre-charge voltage to the output node, the buffer provides the second signal to the output node.
8. The DDI of claim 1 , wherein, prior to a first time at which the control signal transitions from a first level to a second level, the pre-charge controller provides the pre-charge voltage to the output node, the second signal is not provided to the output node, and the switch control signal has the pre-charge voltage.
9. The DDI of claim 1 , wherein at the first time, the pre-charge controller blocks the pre-charge voltage to the output node, and the buffer provides the second signal to the output node.
10. The DDI of claim 9 , wherein, after the first time, the switch control signal has the second voltage and the control signal is at the second level.
11. The DDI of claim 1 , wherein at a second time at which the control signal transitions to the first level from the second level, the pre-charge controller provides the pre-charge voltage to the output node, and the second signal is not provided to the output node.
12. The DDI of claim 11 , wherein, at a third time after the second time, the pre-charge controller blocks the pre-charge voltage to the output node based on or in response to the pre-charge control signal, and the buffer provides the second signal to the output node.
13. The DDI of claim 12 , wherein from the second time to the third time, the switch control signal has a voltage that falls to the pre-charge voltage.
14. The DDI of claim 13 , wherein the voltage of the switch control signal falls to the first voltage after the third time.
15. A display driver integrated circuit (DDI) comprising:
a control signal supply unit configured to generate a plurality of control signals;
a plurality of level shifter units configured to convert a level of the plurality of control signals and generate a plurality of switch control signals;
a voltage generator including switches that are turned on or off based on or in response to the plurality of switch control signals and configured to generate a plurality of voltages based on or in response to a process or operation of the switches; and
a gate driver configured to receive at least one of the plurality of voltages,
wherein each of the level shifter units includes:
a level shifter configured to output a first signal based on or in response to a corresponding one of the control signals;
a buffer configured to buffer the first signal and selectively output a second signal to an output node based on or in response to a buffer control signal; and
a pre-charge controller configured to selectively provide a pre-charge voltage to the output node and generate the buffer control signal based on or in response to the pre-charge control signal,
the pre-charge voltage is higher than the first voltage and is lower than the second voltage, and
the output node is connected to a corresponding one of the switches.
16. The DDI of claim 15 , wherein the pre-charge controller includes:
an inverter configured to invert the pre-charge control signal and output the buffer control signal; and
a positive-polarity control terminal configured to receive the pre-charge control signal, a negative-polarity control terminal configured to receive the buffer control signal, an input terminal configured to receive the pre-charge voltage, and an output terminal connected to the output node.
17. The DDI of claim 15 , wherein the first voltage is a negative voltage, the second voltage is a positive voltage, and the pre-charge voltage is a ground voltage.
18. The DDI of claim 15 , wherein when the pre-charge controller provides the pre-charge voltage to the output node, the buffer performs a pre-charge process or operation in which the second signal is not provided to the output node, and
when the pre-charge controller blocks the pre-charge voltage to the output node, the buffer provides the second signal to the output node.
19. The DDI of claim 18 , wherein the pre-charge controller performs pre-charge process or operation in a non-overlap time or period between successive assertions of the control signals.
20. A display apparatus comprising:
a display panel including gate lines, data lines, and pixels connected to the gate lines and the data lines and in a matrix including rows and columns; and
the DDI of claim 1 , configured to drive the display panel.