Peking University

Shenzhen China Star Optoelectronics Technology Co., Ltd.

Zhijin Hu

Shengdong Zhang

Congwei Liao

Wenjie Li

Junmei Li

Shijie Cao

Chang-yeh Lee

Limei Zeng

Chuanli Leng

Changyeh Lee

An organic light emitting diode panel, a gate driver circuit and a gate driver circuit unit are disclosed, where the gate driver circuit includes a scanning signal generating unit for generating a scanning signal, transmitting a first clock signal to a scanning signal output terminal under the control of a pulse signal, and pulling down and maintaining the voltage of the scanning signal output terminal at a low voltage level under the control of a second clock signal. The gate driver circuit unit also includes a light emitting signal generating unit for generating a light emitting signal, pulling down the voltage of the light emitting signal output terminal under the control of the pulse signal, and charging the light emitting signal output terminal under the control of the second clock signal.

Organic light emitting diode panel, gate driver circuit and unit thereof

The present application provides a gate driver circuit comprising at least one cascaded gate driver circuit unit. The low-level-holding enabling terminal of the gate driver circuit unit is connected to an adaptive voltage generating module. The adaptive voltage generating module generates a self-compensating voltage according to its constant current source and transmits to the low-level-holding enabling terminal, so as to provide an effective voltage level to the low-level-holding enabling terminal. Because the threshold voltage shift caused by pulling-down transistors in the low-level-holding module is embodied at the low-level-holding enabling terminal, the adaptive voltage generating module generates a self-compensating voltage with its constant current source according to the threshold voltage to compensate the increase of the threshold voltage. As such, the overdrive voltage of the pulling-down the transistors keep constant which provides good pulling-down performance, and consequently the lifetime of the gate driver circuit is prolonged.

Gate driving circuit, unit thereof, and display device

The present application discloses a shift register and units thereof, wherein low voltage level maintaining module () includes: a first maintaining unit () and a second maintaining unit (), configured to maintain a signal output terminal and/or the controlling terminal (Q) of the driving module () at low voltage level when an effective level is received. A threshold voltage sensing module () is coupled between the first maintaining unit () and the second maintaining unit (), the threshold voltage sensing module () is configured to control its signal output terminal to provide an effective level to the second maintain-enabling terminal (P) according to threshold voltage shift of the first maintaining unit () sensed. Therefore, low voltage maintaining module () may endure a greater threshold voltage shift, and the life span of the circuit is extended. The present application further discloses a display device and a voltage regulating circuit.

Shift register, unit thereof, and display device

A controllable voltage source, comprising a control module (), a storage module () and an output module (); the control module () is coupled between a high level end and a low level end; the storage module () comprises a storage capacitor; two ends of the storage capacitor are respectively coupled to the control module () to form a first terminal and a second terminal; the output module () is coupled to the second terminal, and the signal output end thereof is used to output to an external circuit the voltage signal of the controllable voltage source; the control module () responds the effective level of a first clock signal so as to enable the first terminal to be coupled to the high level end, and the first terminal is charged from the high level end; the control module () responds the effective level of a second clock signal so as to enable the second terminal to be coupled to the high level end, and the second terminal is charged from the high level end; and the first terminal is coupled to the low level end and discharges via the low level end. The effective level of the first clock signal does not overlap with the effective level of the second clock signal. Also disclosed are a shift register and unit thereof, and display based on the controllable voltage source.

Controllable voltage source, shift register and unit thereof, and display

A shift register is disclosed. The shift register comprises a multistage shift register units. Each of the stage shift register unit comprises: a driving module, charging to the driving signal via the first clock signal based on the driving control signal; an input module, outputting the driving control signal based on the second clock signal and the first control signal; a low level maintenance module, keeping the potential of the driving signal at the low level potential of the second reference. The shift register can avoid the leakage from the first output end, decrease the raising time of the driving signal and occupy the small area.

Shift register

A photoelectric sensor and a display panel comprise: a pulse transmission unit comprising a control node, after obtaining a driving voltage, the control node of the pulse transmission unit transmitting first clock signals to a signal output terminal; a pulse control unit configured to receive scanning signals from a signal input terminal and charging the control node of the pulse transmission unit so as to provide the driving voltage; and photoelectric sensing unit configured to provide a leakage current in response to the intensity of external illumination when receiving the external illumination, the leakage current discharging the control node of the pulse transmission unit, so that the voltage at the control node of the pulse transmission unit is less than the driving voltage after a period of time. The circuit of the photoelectric sensor utilizes the existing scanning signals and clock signals of a conventional display panel, with no need for an extra control signal, and therefore the circuit is simple in structure, and more suitable for being integrated on the display panel.

Photoelectric sensor and display panel

An ultraviolet light sensing circuit and sensing system. The ultraviolet light sensing circuit comprises a modulation unit and a phase delay unit, wherein the modulation unit comprises a first stage of inverter which is used for sensing ultraviolet light and is used as a voltage feedback modulation stage; and the phase delay unit comprises N stages of inverters which are connected in sequence, where N is an even number which is greater than or equal to 2. The modulation unit is connected to the phase delay unit in sequence, and the output voltage of the phase delay unit is fed to the modulation unit; and the modulation unit is modulated by a control signal which is a pulse signal. The ultraviolet light sensing circuit and sensing system can be used for ultraviolet light information communications. The ultraviolet light sensing circuit can sense ultraviolet light signals and output amplitude modulation wave signals.

Ultraviolet light sensing circuit and sensing system

A gate driving circuit and a display device are disclosed. The gate driving circuit includes a control module for pulling down the level of the second control node to be at the low level before the gate strobe signals are outputted and during the output period of the gate cutoff signals. In this way, the second pull-down control end of the low level maintaining module is pulled down to be at the low levels, and the low level maintaining module is in the off state. In this way, the electrical leakage of the low level maintaining module may be reduced so as to decrease the output delay of the gate signals and to enhance the efficiency of the circuit.

Gate driving circuits and display devices

An adaptive voltage source, comprising a signal output end, and a reference resistance forming circuit and a sensing module connected in series between a voltage source and a low power level; the sensing module comprises a sensing end coupled to a transistor to be sensed to sense the threshold voltage drift of the transistor to be sensed in a device circuit; the equivalent resistance of the sensing module increases with the increase of the sensed threshold voltage drift; and the signal output end is coupled to a first node coupled to the reference resistance forming circuit and the sensing module, and is used to output adaptive voltage. The output adaptive voltage is adjusted via the threshold voltage drift sensed by the sensing module. Based on the circuit, also disclosed are a shift register and unit thereof, and display.

Adaptive voltage source, shift register and unit thereof, and display

The present invention provides a gate driver on array (GOA) circuit and a display panel with the GOA circuit. The driver circuit includes multiple stages of gate driver units and multiple stages of supplementary gate driver units connected in cascade, in which the nth stage gate driver unit includes a driving unit () and a pull-down unit () and the mth stage supplementary gate driver unit includes a supplementary driving unit () and a supplementary pull-down unit (). The GOA circuit according to the present invention adopts a dual-pull-down architecture so that thin-film transistors contained in pull-down units and supplementary pull-down units of the circuit can be set in an operation environment featuring dual polarity electrical biasing to effectively suppress threshold voltage drifting of the thin-film transistors of the pull-down units and the supplementary pull-down units and extend the lifespan of circuit thereby making the circuit better meet the needs of large- and medium-sized display panels. Further, the circuit has a simple structure and reduced power consumption and is also fit to low temperature and high temperature operations.

Growing community of inventors

Guangdong, China

Zhijin Hu