Display driver, electronic apparatus, and mobile body

Patent metadata

Field	Value
Publication number	US-10861363-B2
Application number	US-201916449634-A
Country	US
Kind code	B2
Filing date	Jun 24, 2019
Priority date	Jun 25, 2018
Publication date	Dec 8, 2020
Grant date	Dec 8, 2020

Abstract

A display driver (100) includes a drive circuit (130) that drives an electro-optical panel (200), a control circuit (110) that controls the drive circuit (130), an error detection circuit (115) that detects an error in the display driver (100), and a counter (125) that performs count processing with respect to information regarding the number of times of error detection in an operating period of the display driver (100). The control circuit performs control such that information regarding the accumulated number of times of detection of the error is stored in a nonvolatile memory that can retain storage contents even if power is not supplied, based on the information regarding the number of times of detection.

First claim

What is claimed is:

1. A display driver including a drive circuit that drives an electro-optical panel and a control circuit that controls the drive circuit, the display driver comprising:
an error detection circuit configured to detect an error in the display driver; and
a counter configured to perform count processing with respect to information regarding accumulated number of times of detection of the error in operation of the display driver, the accumulated number including a number of times of detection of the error that is accumulated during a first operation period and stored in a nonvolatile memory and a number of times of detection of the error that is accumulated during a second operation period, the second operation period being a period after the first operation period has ended and a period at the beginning of which the number of times of detection of the error accumulated during the first operation period is read out from the nonvolatile memory to be updated,
wherein the control circuit is configured to perform control such that the information regarding the accumulated number of times of detection of the error is stored in the nonvolatile memory based on the number of times of detection accumulated during the first operation period, and such that the nonvolatile memory retains storage contents even if power is not supplied.

2. The display driver according to claim 1 ,
wherein the control circuit, after a reset of the display driver is cancelled, reads out the information regarding the accumulated number of times of detection from the nonvolatile memory, and updates the information regarding the accumulated number of times of detection stored in the nonvolatile memory, based on the information regarding the number of times of detection.

3. The display driver according to claim 2 ,
wherein the control circuit updates the information regarding the accumulated number of times of detection stored in the nonvolatile memory in a period from when display of the electro-optical panel is turned off until the display driver is reset.

4. The display driver according to claim 2 ,
wherein the control circuit regularly updates the information regarding the accumulated number of times of detection stored in the nonvolatile memory in the operating period.

5. The display driver according to claim 2 ,
wherein the control circuit updates the information regarding the accumulated number of times of detection stored in the nonvolatile memory on the condition that a number of times of detection indicated by the information regarding the number of times of detection exceeds a threshold value.

6. The display driver according to claim 1 ,
wherein the control circuit updates the information regarding the accumulated number of times of detection by writing information based on the information regarding the number of times of detection in a memory region of the nonvolatile memory that is different from a memory region in which the information regarding the accumulated number of times of detection before updating is stored.

7. The display driver according to claim 1 ,
wherein, when the information regarding the accumulated number of times of detection is stored in first to mth bits (m is an integer of n−1 or less) of first to nth bits (n is an integer of 2 or more) in the nonvolatile memory, the control circuit updates the information regarding the accumulated number of times of detection by performing writing to a m+1th bit of the first to nth bits.

8. The display driver according to claim 1 ,
wherein the control circuit, upon determining that the display driver is in an anomalous state based on the information regarding the accumulated number of times of detection, performs reporting processing of the anomalous state.

9. The display driver according to claim 1 ,
wherein the operating period is a period including a reset-cancelled period of the display driver.

10. The display driver according to claim 1 ,
wherein the counter is initialized when the display driver is reset.

11. The display driver according to claim 1 ,
wherein the error is at least one of a register error, a state machine error, a voltage error, a clock signal error, and a display data error.

12. An electronic apparatus comprising:
the display driver according to claim 1 ; and
a processing device configured to control the display driver.

13. The electronic apparatus according to claim 12 ,
wherein the processing device performs, upon determining that the display driver is in an anomalous state based on the information regarding the accumulated number of times of detection, reporting processing associated with the anomalous state.

14. A mobile body comprising:
a display driver according to claim 1 ; and
a processing device configured to control the display driver.

Assignees

• Seiko Epson Corp

Inventors

• Muraki Norichika

Classifications

• G09G3/20 Primary

  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 title

• G09G3/3611

  Control of matrices with row and column drivers · CPC title

• G09G3/32

  semiconductive, e.g. using light-emitting diodes [LED] · CPC title

• G09G2330/12

  Test circuits or failure detection circuits included in a display system, as permanent part thereof · CPC title

• G09G2380/10

  Automotive applications · CPC title