Pixel driver circuit and pixel circuit having control circuit coupled to supply voltage

• US 8,890,220 B2
• Filed: 09/26/2013
• Issued: 11/18/2014
• Est. Priority Date: 02/16/2001
• Status: Expired due to Term

• Current Assignee: IGNIS Innovation Incorporated
• Original Assignee: IGNIS Innovation Incorporated
• Inventors: Nathan, Arokia, Servati, Peyman, Sakariya, Kapil, Kumar, Anil
• Primary Examiner(s): HA, NATHAN W
• Application Number:
  US14/038,651
• Publication Number:
  US 20140028217A1
• Time in Patent Office: 418 Days
• Field of Search: 257/40, 257/355, 257/57, 257/59, 257/292
• US Class Current: 257/292
• CPC Class Codes: G09G 2300/0804 Sub-multiplexed active matrix panel, i.e. wherein one active driving circuit is used at pixel level for multiple image producing elements
• CPC Class Codes: G09G 2300/0819 used for counteracting undesired variations, e.g. feedback or autozeroing
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2320/0204 Compensation of DC component across the pixels in flat panels
• CPC Class Codes: G09G 2320/0223 Compensation for problems related to R-C delay and attenuation in electrodes of matrix panels, e.g. in gate electrodes or on-substrate video signal electrodes
• CPC Class Codes: G09G 2320/045 Compensation of drifts in the characteristics of light emitting or modulating elements
• CPC Class Codes: G09G 3/035 for flexible display surfaces
• CPC Class Codes: G09G 3/3233 with pixel circuitry controlling the current through the light-emitting element
• CPC Class Codes: G09G 3/3241 the current through the light-emitting element being set using a data current provided by the data driver, e.g. by using a two-transistor current mirror
• CPC Class Codes: H01L 27/12 the substrate being other than a semiconductor body, e.g. an insulating body
• CPC Class Codes: H01L 29/78648 arranged on opposing sides of the channel
• CPC Class Codes: H03K 17/162 without feedback from the output circuit to the control circuit
• CPC Class Codes: H03K 17/6871 the output circuit comprising more than one controlled field-effect transistor
• CPC Class Codes: H05B 45/60 Circuit arrangements for operating LEDs comprising organic material, e.g. for operating organic light-emitting diodes [OLED] or polymer light-emitting diodes [PLED]
• CPC Class Codes: H10K 19/10 comprising field-effect transistors
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/131 Interconnections, e.g. wiring lines or terminals

Abstract

A pixel driver circuit for driving a light-emitting element and a pixel circuit having the pixel driver circuit are provided. The pixel driver circuit includes a data line, address lines, switch thin film transistors, feedback thin film transistors and drive thin film transistors. The pixel circuit may include an organic light emitting diode, which is driven by the pixel driver circuit.

Claims

1. A control circuit coupled to a supply voltage, comprising a load and a first transistor coupled in series to said supply voltage, said first transistor having a gate and the load having a diode configuration and being connected to a terminal of the first transistor other than the gate,

a second transistor directly connected to said gate of said first transistor for connecting a bias line to the said gate, and

a third transistor directly connected to a node between said load and said first transistor, wherein during a programming operation the second transistor and the third transistor are on, the third transistor controlling the voltage at said node so that the load is off during the programming operation, and wherein during a driving operation the second and third transistors are off.

2. The control circuit of claim 1 which includes a second load and a fourth transistor coupled in series to said supply voltage, said fourth transistor having a gate coupled to said second transistor.

3. The control circuit of claim 1, wherein the load is a diode-connected transistor.

4. The control circuit of claim 1, further comprising a driver connected to a light emitting device, and wherein during the driving operation the driver is turned on to cause the light emitting device to emit light.

5. The control circuit of claim 4, wherein the driver is a fourth transistor and a gate of the fourth transistor is connected between the first and second transistors.

6. The control circuit of claim 1, wherein during the programming operation, a voltage at a drain terminal and a source terminal of the third transistor becomes equal.

7. The control circuit of claim 1, wherein a gate of the third transistor is connected to a first line and a terminal of the second transistor other than a gate of the second transistor is connected to a second line different from the first line.

8. The control circuit of claim 7, wherein during the driving operation, a current conducted by the driver is substantially the same as that of the first transistor after the second and third transistors are turned off.