Gate driver

About: Gate driver is a research topic. Over the lifetime, 7532 publications have been published within this topic receiving 75854 citations.

Display panel and gate driver therein

Abstract: A gate driver includes cascade-connected driving stages. Each of the driving stages includes a first shift register circuit and a second shift register circuit. The first shift register circuit is configured for outputting a present stage driving signal and a next stage driving signal. The second shift register circuit is electrically coupled to the first shift register circuit and configured for outputting a present stage gate signal, a first next stage gate signal, and a second next stage gate signal. Furthermore, a display panel is also provided herein.

Hybrid Dickson Switched-Capacitor Converter With Wide Conversion Ratio in 65-nm CMOS

Abstract: Hybrid switched-capacitor (SC) converters have shown great promise in achieving high efficiency and power density for dc–dc conversion. By combining an SC stage with an inductor filter stage, benefits from both approaches can be realized. In this work, a hybrid Dickson SC converter with a 4:1 native conversion ratio and regulated output voltage range of 0.3–0.9 V from a 3.4 to 4.2-V lithium-ion battery and the effective switching frequency of 1 MHz was implemented in 65-nm bulk CMOS process. The converter achieves maximum output current of 1.5 A, the power density of 330 mW/mm2, and a peak efficiency of 92.6%. The converter is packaged using flip-chip technology with passive devices co-packaged through a high-density interposer to minimize the packaging parasitics and volume. A segmented gate driver is used to enhance the converter efficiency and reliability by maintaining low-voltage ringing across the power switches. The converter is integrated with closed-loop output voltage regulation, dead-time control, and active capacitor–voltage balancing to maximize the active and passive device utilizations.

Lighting device and liquid crystal display using the same

Abstract: PROBLEM TO BE SOLVED: To provide a lighting device permitting to reduce blurring of movement and tailing in animation display while inhibiting display brightness from falling off, moreover, capable of suppressing power consumption, reducing the weight and size, and prolonging the life of the device, and to provide a liquid crystal display using the same. SOLUTION: A light source control part 22 of a control circuit 16 outputs a luminance control signal to each light source power supply circuit 35-38 in synchronization with latch pulse signals LP outputted to a gate driver 12 from a gate driver control part 18. Based on the inputted luminance control signal, each light source power supply circuit 35-38 changes over the light emitting states of cold cathode tubes 30-33 to any of the 1st to 3rd light emitting states S1-S3 to light an LCD panel 2 from the back surface of the display area. The 1st light emitting state is a turned-off state S1; the 2nd light emitting state a maximum lighting state S2 in which the maximum lighting brightness can be obtained; and the 3rd light emitting state is an intermediate lighting state S3 in which about a half of the 2nd light emitting state can be obtained. COPYRIGHT: (C)2004,JPO&NCIPI

Liquid crystal display device and method for driving the same

Abstract: A liquid crystal display (LCD) device and a method for driving the same are disclosed, which reduce power consumption and improve an image quality. The LCD device includes a liquid crystal panel in which a plurality of sub-pixels is defined by intersection of a plurality of gate lines and a plurality of data lines, and sub-pixels adjacent to each other in a column direction are connected by sharing the plurality of gate lines. A gate driver may sequentially transfer a scan pulse to even-numbered gate lines and then sequentially transferring a scan pulse to odd-numbered gate lines. A data driver may be synchronized with the applied scan pulse in providing data voltage to columns of sub-pixels. The data driver provides the data voltage having different polarities to a neighbor data line during one frame interval such that sub-pixels are driven by a horizontal 2-dot inversion scheme.

Stray Impedance Measurement and Improvement of High-Power IGCT Gate Driver Units

Abstract: Turn-off capability of integrated gate-commutated thyristor is highly dependent on the commutation capability of its gate driver unit (GDU). To enhance it, stray impedance is the crucial limitation, which has not been obtained accurately before. Thus, in this paper, acquisition method of impedance based on experimental measurements was carefully analyzed, including electrolytic and ceramic capacitors, mosfets , printed circuit board, and GCT housing. And each part of stray impedance was obtained based on a series of experiments with 6-inch GCTs and two types of conventional GDUs. To further enhance commutation speed, an improved GDU was developed, reducing the total stray inductance from 0.395 to 0.037 nH, stray resistance from 0.444 to 0.227 mΩ. An extremely high current of 12.5 kA was successfully turned off, which is the maximum turn-off current level so far. Besides, the maximum commutation capability was tested as over 17 kA. Consequently, no further optimization of GDU is necessary. However, there was still about 1.0 nH existing inside the GCT housing we used. A novel housing with lower stray inductance is expected for higher commutation speed in the future.