A Compact Bi-Direction Scannable a-Si:H TFT Gate Driver

Abstract

An integrated a-Si:H thin-film transistors (TFTs) gate driver on array with both forward and backward scanning function is proposed. The single stage of the gate driver only consists of seven TFTs. The bi-direction scannable function is just realized by controlling the turning-on sequence of two input TFTs. Both scanning modes use the same driving TFT for pulling-up and pullingdown the output voltage and the same circuit unit for holding the low level. The proposed gate driver is fabricated in the 4.5 G TFT production line, and the measurements with the fabricated drivers verify the feasibility of the proposed driver.Index Terms-A-Si:H, bi-directional scan, gate driver, thin-film transistors (TFTs).

P‐43: Implementation of Digital Thin‐Film Transistor Integrated Ambient Light Sensor with High Reliability

“…The output signal of the light sensing is basically digital. In addition, the output voltage is generated by bootstrapping principal and certain threshold voltage shift (>10 V) in the switching and driving transistors are tolerable [3]. Further, as the intensity of ambient light is only related with the leakage current of off current, the number of output pulses is almost independent of the threshold voltage and mobility as shown in Eq.…”

“…The voltage of node Q is bootstrapped by C1 and gate-to-source capacitance of T2. Being different from the gate driver circuit published elsewhere [3], [5], the turning on state of T2 can be maintained in the following procedures, as there is no discharging of V Q following the voltage bootstrapping. But V Q is actually decreasing gradually due to the leakage current through T3, which is strongly dependent on the exposed ambient light.…”

“…Thanks to the development of TFT technology in recent years, high performance display with ultrahigh resolution and narrow bezel, and even with flexible forms can be realized [2]. Further, lots of attentions are paid to realize various sensing functions using TFTs for value-added system on display panel (SoP) [3]- [5]. In addition to switching or driving transistors for active matrix displays (AMDs), TFT is also capable of realizing optical, temperature and mechanical sensing functions.…”

Multioutputs single‐stage gate driver on array with wide temperature operable thin‐film‐transistor liquid‐crystal display for high resolution application

“…For the high resolution display application, the thousands micrometer width of the main driving TFT is required to drive the gate line of the panel; the modification results in widening the bezel of panel. One method of a previous research could reduce the pull‐down TFT with single path for pulling up and down in the working period, but the reduced area is limited since a driving block of gate driver has to go with one corresponding noise‐free block per stage. The other way to solve the problem is sharing the noise block for multioutputs by sharing the noise‐free block as shown in Figure …”

1.3: An Evaluation Method of TFT Integrated Gate Driver for UHD Display

“…In recent years, the integration of gate drivers using a-Si:H TFTs becomes popular with TV-display manufactures. Although resistance-capacitance (RC) loading of the display panel is considerably large for UHD TV display, TFT integrated gate driver is still able to fulfill the charging requirement of display matrix by using the voltage bootstrapping method, and the precharging method [3], taking advantage of overlapped multiplephase clock signals. However, up to date, the reliability of TFT integrated gate driver is still of great concern as the TV's continuous-operating-time is much longer than that of the mobile display.…”