公开(公告)号：US11581861B2

公开(公告)日：2023-02-14

申请号：US16935174

申请日：2020-07-21

Applicant: NOVATEK Microelectronics Corp.

Inventor： Ying-Hsiang Wang ,  Tsung-Hau Chang ,  Jung-Hsing Liao

IPC: H03F3/45

Abstract: An operational amplifier includes a first differential input pair, a first switch and a second switch. The first differential input pair includes a first input transistor and a second input transistor. The first input transistor has a gate terminal coupled to an output terminal of the operational amplifier. The second input transistor has a gate terminal. The first switch is coupled between the gate terminal of the first input transistor and the gate terminal of the second input transistor. The second switch is coupled between a first input terminal of the operational amplifier and the gate terminal of the second input transistor.

公开(公告)号：US20220013052A1

公开(公告)日：2022-01-13

申请号：US17117121

申请日：2020-12-10

Applicant: Novatek Microelectronics Corp.

Inventor： Ying-Hsiang Wang ,  Chia-Lun Chang

IPC: G09G3/20

Abstract: A source driver adapted to drive a display panel is provided. The source driver includes an output buffer and a slew rate adjustment circuit. An input terminal of the output buffer receives a driving voltage. An output terminal of the output buffer outputs an output signal adapted to drive the display panel. The slew rate adjustment circuit dynamically adjusts a slew rate of a rising edge of the output signal according to a first setting and dynamically adjusts a slew rate of a falling edge of the output signal according to a second setting independent of the first setting, such that the adjustment to the slew rate of the rising edge of the output signal is independent of the adjustment to the slew rate of the falling edge of the output signal.

公开(公告)号：US11176861B2

公开(公告)日：2021-11-16

申请号：US17088600

申请日：2020-11-04

Applicant: NOVATEK Microelectronics Corp.

Inventor： Syang-Yun Tzeng ,  Cheng-Tsu Hsieh ,  Ching-Wen Hou ,  Ying-Hsiang Wang ,  Ping Chen

IPC: G09G3/00

Abstract: An electronic device includes a substrate and a display driver chip bonded on the substrate. The display driver chip includes a plurality of operational amplifiers, and each of the operational amplifiers has a first stage and a second stage. The first stage includes a first power input terminal. The second stage includes a first power input terminal and an output terminal for outputting an output voltage. The first power input terminal of the first stage is connected to a first metal trace of the substrate, and the first power input terminal of the second stage is connected to a second metal trace of the substrate. The first power input terminal of the first stage and the first power input terminal of the second stage are both provided with a first voltage level.

公开(公告)号：US11081036B1

公开(公告)日：2021-08-03

申请号：US16934038

申请日：2020-07-21

Applicant: Novatek Microelectronics Corp.

Inventor： Ying-Hsiang Wang

IPC: G09G3/20 ,  H03K5/24 ,  H03F3/45

Abstract: The disclosure provides a slew rate enhancement apparatus that is connected to an operational amplifier that receives an input signal and generates an output signal according to the input signal for driving a pixel. The slew rate enhancement apparatus comprises a signal edge detector, a comparator, an adjustment unit. The signal edge detector is coupled to the operational amplifier and configured to detect a signal edge and outputting a difference signal corresponding to a difference between the input and output signals. The comparator is coupled to the signal edge detector to receive the difference signal and configured to generate a control signal according to the difference signal. The adjustment unit is coupled to the comparator to receive the control signal, and configured to couple a compensation signal generated by a current source to the operational amplifier according to the control signal to enhance a slew rate of the operation amplifier.