Level shifter, digital-to-analog converter, and buffer amplifier, and source driver and electronic device including the same
A level shifter, a digital-to-analog converter (DAC), and a buffer amplifier, and a source driver and an electronic device including the same are provided. The source driver includes a level shifter configured to receive digital bits and provide a level-shifted output signal; a DAC including a resistor string configured to provide a plurality of gradation voltages formed by an upper limit voltage and a lower limit voltage being received through one end and the other end, and an N-type metal oxide semiconductor (NMOS) switch and a P-type MOS (PMOS) switch configured to be controlled by the level-shifted output signal and output a gradation voltage corresponding to the level-shifted output signal; and an amplifier configured to amplify a signal provided by the digital-to-analog converter, and the lower limit voltage is provided to a body electrode of the NMOS switch.
1. A source driver that drives a display panel, comprising:
a level shifter configured to receive digital bits and provide a level-shifted output signal;
a digital-to-analog converter including a resistor string configured to provide a plurality of gradation voltages formed by an upper limit voltage and a lower limit voltage being received through one end and the other end, and an N-type metal oxide semiconductor (NMOS) switch and a P-type MOS (PMOS) switch configured to be controlled by the level-shifted output signal and output a gradation voltage corresponding to the level-shifted output signal; and
an amplifier configured to amplify a signal provided by the digital-to-analog converter,
wherein the lower limit voltage is provided to a body electrode of the NMOS switch,
wherein the level shifter is driven by a first voltage and a second voltage that is smaller than the first voltage, and the level-shifted output signal swings between the first voltage and the second voltage.
2. The source driver of claim 1 , wherein the first voltage is the same as the upper limit voltage, and the second voltage is the same as the lower limit voltage.
3. The source driver of claim 1 , wherein the level shifter comprises an NMOS transistor in which the second voltage is provided to a body electrode thereof.
4. The source driver of claim 1 , wherein the NMOS switch is arranged in the same well, and the lower limit voltage is provided as a well bias voltage of the well.
5. The source driver of claim 1 , wherein an NMOS switch and a PMOS switch arranged in the same well have an enduring voltage corresponding to a difference between the upper limit voltage and the lower limit voltage.
6. The source driver of claim 1 , wherein the lower limit voltage is a minimum voltage among the plurality of gradation voltages, and the upper limit voltage is a maximum voltage among the plurality of gradation voltages.
7. The source driver of claim 1 , wherein the amplifier is a buffer having unity gain.
8. The source driver of claim 1 , wherein the amplifier is driven by receiving the upper limit voltage and the lower limit voltage, and the amplifier is formed using a device having an enduring voltage corresponding to a difference between the upper limit voltage and the lower limit voltage.
9. The source driver of claim 1 , wherein the amplifier comprises a plurality of NMOS transistors, the NMOS transistors are arranged in the same well, and the lower limit voltage, which is a well bias voltage provided to the well, is provided to body electrodes of the NMOS transistors.
10. An electronic device, comprising:
a source driver including a level shifter configured to receive digital bits and provide a level-shifted output signal, a digital-to-analog converter including a resistor string configured to provide a plurality of gradation voltages formed by an upper limit voltage and a lower limit voltage being received through one end and the other end, and a plurality of switches configured to be controlled by the level-shifted output signal and output a gradation voltage corresponding to the level-shifted output signal, and an amplifier configured to amplify a signal provided from the digital-to-analog converter, wherein the switches include NMOS switches in which the lower limit voltage is provided to body electrodes, and
a display panel driven by the source driver,
wherein the plurality of switches have an enduring voltage corresponding to a difference between the upper limit voltage and the lower limit voltage.
11. The electronic device of claim 10 , wherein the level shifter is driven by the upper limit voltage and a lower limit voltage that is smaller than the upper limit voltage, and is formed using a device having an enduring voltage corresponding to a difference between the upper limit voltage and the lower limit voltage.
12. The electronic device of claim 10 , wherein the amplifier is driven by the upper limit voltage and a lower limit voltage that is smaller than the upper limit voltage, and is formed using a device having an enduring voltage corresponding to a difference between the upper limit voltage and the lower limit voltage.