LCD SOURCE DRIVER FEEDBACK SYSTEM AND METHOD

• US 20140312908A1
• Filed: 03/27/2014
• Published: 10/23/2014
• Est. Priority Date: 03/27/2013
• Status: Active Grant

• Current Assignee: Mercury Mission Systems LLC (Mercury Systems, Incorporated)
• Original Assignee: American Panel Corporation (Mercury Systems, Incorporated)
• Inventors: Williams, David, Lemons, Charles, Baek, Gary, Preston, Steve
• Granted Patent: US 10,121,399 B2
• Time in Patent Office: Days
• US Class Current: 324/414
• CPC Class Codes: G09G 2310/0275 Details of drivers for data electrodes, other than drivers for liquid crystal, plasma or OLED displays, not related to handling digital grey scale data or to communication of data to the pixels by means of a current
• CPC Class Codes: G09G 2330/12 Test circuits or failure detection circuits included in a display system, as permanent part thereof
• CPC Class Codes: G09G 2380/12 Avionics applications
• CPC Class Codes: G09G 3/006 Electronic inspection or testing of displays and display drivers, e.g. of LED or LCD displays testing individual LED's G01R31/2635; testing lamps G01R31/44; testing of optical features of LCD displays G02F1/1309
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
• CPC Class Codes: G09G 3/3275 Details of drivers for data electrodes
• CPC Class Codes: G09G 3/3685 Details of drivers for data electrodes

Abstract

An electrical assembly and method for detecting failures in an LCD source driver is disclosed herein. A plurality of active channels are placed on the source driver which communicate electronically with an LCD. At least one dummy channel may be placed on the source driver which is driven with an original signal. A microprocessor may then receive the dummy channel and compare the received dummy channel signal to the original signal. An error message may be transmitted when the received dummy channel signal does not match the original signal. Alternatively, the source driver may be provided with a split active channel which is provided with an original signal that is split into an active split channel and a dummy split channel. While the active split channel is sent to the LCD, the dummy split channel is sent to the microprocessor for comparison with the original signal.

Claims

1. A method for detecting a failure in an LCD source driver comprising the steps of:

providing at least one dummy channel in addition to the active channels on the source driver;

driving the dummy channel and active channels with original signals;

receiving the dummy channel signal as a received dummy channel signal; and

comparing the received dummy channel signal with the original signal.

2. The method of claim 1 further comprising the steps of:

converting the received dummy channel signal from analog to digital before comparing with the original signal.

3. The method of claim 1 further comprising the step of:

alerting upstream logic that a failure has occurred when the received dummy channel signal does not match the original signal.

4. The method of claim 1 further comprising the step of:

splitting an active channel so as to produce a resulting active channel signal and dummy channel signal based on the same original signal.

5. The method of claim 4 further comprising the steps of:

receiving the dummy channel signal and comparing it with the original signal; and

receiving the active channel signal at the LCD.

6. An electrical assembly for detecting failures in an LCD source driver comprising:

a plurality of active channels on the source driver which communicate electronically with an LCD;

a dummy channel on the source driver which is driven with an original signal; and

a microprocessor which receives the dummy channel and compares the received dummy channel signal to the original signal.

7. The electrical assembly of claim 6 further comprising:

an analog to digital converter which digitizes the received dummy channel signal before comparing it to the original signal.

8. The electrical assembly of claim 6 wherein:

the microprocessor is located on a display interface board.

9. The electrical assembly of claim 6 further comprising:

a second dummy channel on the source driver which is driven with a second original signal; and

wherein the microprocessor additionally receives the second dummy channel and compares the received second dummy channel to the second original signal.

10. The electrical assembly of claim 6 wherein:

the microprocessor is adapted to transmit an error message when the received dummy channel signal does not match the original signal.

11. The electrical assembly of claim 9 wherein:

the microprocessor is adapted to transmit an error message when either (1) the received dummy channel signal does not match the original signal or (2) the received second dummy channel signal does not match the second original signal.

12. An electrical assembly for detecting failures in an LCD source driver comprising:

a plurality of active channels on the source driver which communicate electronically with an LCD;

a split active channel on the source driver which is provided with an original signal and splits this into an active split channel and a dummy split channel where the active split channel is sent to the LCD; and

a microprocessor which receives the dummy split channel and compares the received dummy split channel signal to the original signal.

13. The electrical assembly of claim 12 further comprising:

an analog to digital converter which digitizes the received dummy split channel signal before comparing it to the original signal.

14. The electrical assembly of claim 12 wherein:

the microprocessor is located on a display interface board.

15. The electrical assembly of claim 12 further comprising:

a second split active channel on the source driver which is provided with a second original signal and splits this into a second active split channel and a second dummy split channel where the second active split channel is sent to the LCD; and

wherein the microprocessor additionally receives the second dummy split channel and compares the received second dummy split channel to the second original signal.

16. The electrical assembly of claim 12 wherein:

the microprocessor is adapted to transmit an error message when the received dummy split channel signal does not match the original signal.

17. The electrical assembly of claim 15 wherein:

the microprocessor is adapted to transmit an error message when either (1) the received dummy split channel signal does not match the original signal or (2) the received second dummy split channel signal does not match the second original signal.

18. The electrical assembly of claim 12 wherein:

the original signal is data for generating an image on the LCD.

19. The electrical assembly of claim 17 wherein:

the error message comprises any one of the following;

a blank screen, flashing lights, a textual error message on the LCD, or an audible warning.