Thin-film transistor circuitry with reduced sensitivity to variance in transistor threshold voltage
US6307322A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 28, 1999 |
| Grant date | Oct 23, 2001 |
| Priority date | — |
| Expiry date | Dec 28, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/042
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A circuit design technique polysilicon thin-film transistor (TFT) circuitry produces circuits that are relatively less sensitive to threshold variations among the TFT's than circuits designed using conventional techniques. The circuit is designed such that thin-film transistors that are sensitive to threshold variations are made larger than other thin-film transistors in the circuitry to minimize threshold variations among similar transistors implemented in the circuit. In one embodiment, a pixel structure for an active matrix display device implemented in polysilicon includes two transistors, a select transistor and a drive transistor. The drive transistor in the pixel structure is a thin film metal oxide silicon (MOS) transistor that includes a gate to source capacitance sufficient to hold an electrical potential which keeps the transistor in a conducting state for an image field interval. One embodiment of the pixel structure includes only the select transistor and the drive transistor. The pixel storage capacitance is entirely realized by the gate to source capacitance of the drive transistor. Another embodiment of the pixel structure includes a capacitor which is much smaller …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.