US 2019/0295490 A1 · GAMMA ADJUSTMENT CIRCUIT AND DISPLAY DRIVER CIRCUIT USING THE SAME

Abstract

A gamma adjustment circuit is provided. The gamma adjustment circuit includes: a first node; a second node different from the first node; a first decoder to which a first voltage signal and a second voltage signal are provided and which outputs either one of the first voltage signal and the second voltage signal as a third voltage signal; an amplifier which receives the third voltage signal as a positive input and outputs a fourth voltage signal; a second decoder which receives the fourth voltage signal and outputs the provided fourth voltage signal as a fifth voltage signal to one of the first and second nodes; a third decoder which is connected to the first and second nodes, receives the fifth voltage signal from one of the first and second nodes, and outputs the fifth voltage signal to a negative input terminal of the amplifier as a sixth voltage signal; and a first resistor connected between the first node and the second node.

Claims20

Dependent claims

A gamma adjustment circuit comprising:

a first decoder configured to receive a first voltage signal and a second voltage signal, and output one of the first voltage signal and the second voltage signal as a third voltage signal;
an amplifier including a positive input and a negative input, the positive input configured to receive the third voltage signal, and to output a fourth voltage signal;
a second decoder configured to output the fourth voltage signal to one of a first node and a second node as a fifth voltage signal;
a third decoder connected to the first node and the second node, the third decoder configured to output the fifth voltage signal to the negative input of the amplifier as a sixth voltage signal;
and
a first resistor connected between the first node and the second node.

3 more elements

A display driver circuit comprising:

a source driver integrated circuit (IC) configured to transmit an analog voltage to a display panel;
a gate driver integrated circuit (IC) configured to control a gate of the display panel so that the analog voltage is provided to a storage device associated with the display panel;
a controller configured to control the source driver IC and the gate driver IC based on a signal received from a host;
and
a gamma adjustment circuit configured to transmit the analog voltage to the source driver IC, the gamma adjustment circuit including,
an amplifier including a cascade differential amplifier and a common source (CS) amplifier, the cascade differential amplifier configured to receive a first signal, and to generate a second signal based on the first signal, the CS amplifier configured to receive the second signal, and to generate a third signal based on the second signal,
a first decoder including a first output terminal and a second output terminal, the first decoder configured to receive the third signal from the CS amplifier, the first decoder configured to select, based on a first selection signal, one of the first output terminal and the second output terminal as a selected output terminal, to provide the third signal to the selected output terminal as a fourth signal, and
a second decoder including a first input terminal and a second input terminal.

5 more elements

A display driver circuit comprising:

a source driver integrated circuit (IC) configured to transmit an analog voltage to a display panel;
a gate driver integrated circuit (IC) configured to control a gate of the display panel so that the analog voltage is provided to a storage device associated with the display panel;
a controller configured to control the source driver IC and the gate driver IC based on a signal received from a host;
and
a gamma adjustment circuit configured to transmit the analog voltage to the source driver IC, the gamma adjustment circuit including,
a first decoder including an input terminal and an output terminal,
a second decoder including an input terminal and an output terminal, the input terminal of the second decoder being connected, via at least a first node and a second node, to the output terminal of the first decoder, the first node and the second node having a first resistor connected therebetween, and
an amplifier including a negative input terminal, a positive input terminal and an output terminal, the negative input terminal of the amplifier being connected to the output terminal of the second decoder, and the output terminal of the amplifier being connected to the input terminal of the first decoder.

5 more elements

Dependencies are inferred from the claim text.

Gamma adjustment circuit and display driver circuit using the same

Life of this patent

Gamma adjustment circuit and display driver circuit using the same

Life of this patent

Abstract

Claims20