IP Library Granted Patent US 7,812,805
Granted Patent B2
US 7,812,805 · App. 11/251,890 · Granted Oct 12, 2010

Driver circuit and display device

View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 7,812,805
App. No.
11/251,890
Granted
Oct 12, 2010
Kind
B2
Abstract

To provide a driver circuit that enables reduction in the number of elements formed through a high-voltage process and in chip size. An embodiment of the present invention relates to a driver circuit for inversion-driving a liquid crystal display panel, including: a positive-polarity line transmitting a positive display signal relative to a common electrode signal; a negative-polarity line transmitting a negative display signal relative to the common electrode signal; a dot inversion switch circuit switching the positive-polarity line and the negative-polarity line from each other to be connected with a source line; a charge recovery circuit connected with the positive-polarity line through a positive charge recovery switch and connected with the negative-polarity line through a negative charge recovery switch; and a common short circuit connecting the positive-polarity line and the negative-polarity line with a common electrode.

Claims (15)

1. A driver circuit for inversion-driving a display panel, comprising:

a common short circuit selectively connecting each of a positive-polarity line and a negative polarity line to a common electrode that is connected to a common electrode driver for the display panel, the positive-polarity line transmitting a positive display signal relative to a reference voltage and the negative-polarity line transmitting a negative display signal relative to the reference voltage;

a charge recovery circuit that receives outputs from the common short circuit, the positive-polarity line being connected to the charge recovery circuit through a first switching element and the negative-polarity line being connected to the charge recovery circuit through second switching element; and

a switching part that receives outputs from the charge recovery circuit and selectively connects the positive-polarity line and the negative-polarity line with a source line.

2. The driver circuit according to claim 1 , wherein the reference voltage is one of a common voltage applied to the common electrode and a system ground voltage.

3. The driver circuit according to claim 1 , further comprising at an input to the common short circuit:

a positive-polarity operational amplifier connected with the positive-polarity line and outputting the positive display signal; and

a negative-polarity operational amplifier connected with the negative-polarity line and outputting the negative display signal.

4. The driver circuit according to claim 1 ,

wherein the charge recovery part includes charge recovery lines and charge recovery capacitors, and

each of the charge recovery lines and the charge recovery capacitors are separately provided for positive charge recovery and negative charge recovery.

5. The driver circuit according to claim 4 , wherein the switching part selects the charge recovery capacitor for the positive charge recovery or the charge recovery capacitor for the negative charge recovery.

6. A display device comprising the driver circuit according to claim 4 , wherein the switching part, the first switching element, and the second switching element are provided on a substrate constituting the display panel, and

the charge recovery capacitors are externally connected with the substrate.

7. A display device, comprising the driver circuit according to claim 1 .

Assignments (2)
CHANGE OF NAME Recorded Nov 11, 2010
From: NEC ELECTRONICS CORPORATION
To: RENESAS ELECTRONICS CORPORATION
Reel/Frame 025346/0877 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 18, 2005
From: MIURA, MAKOTO
To: NEC ELECTRONICS CORPORATION
Reel/Frame 017112/0552 →