JPH02235480A - Method for writing defect address for solid-stage image pickup device - Google Patents

Abstract

PURPOSE:To surely correct a defect of a solid-state image pickup element electrically by providing an input terminal through which a data to be written in a nonvolatile memory is inputted, detecting an address of a defect and writing the address into a nonvolatile memory through the input terminal. CONSTITUTION:A uniform light with various intensities radiates to a solid-stage image pickup element CCD 2 to detect a defect address of the CCD 2 based on a video signal obtained from an output terminal T1 and a horizontal and vertical synchronizing pulse and a data representing odd and even fields obtained from a timing generating circuit 7 through an output terminal T2 provided newly to the solid-state image pickup element 1. Then the data of the detected defect address, the data representing odd and even fields or the data of a reference point, that is, the data of a distance on the horizontal scanning line between a scanning start point of the 1st horizontal scanning line of the field of the CCD 2 and one or plural points of defects adjacent to each other succeeding to the start point on the horizontal scanning line and the data representing odd and even fields are fed to an EEPROM 5 through an input terminal T3 provided newly to the device 1 and written therein.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a solid-state imaging device equipped with a solid-state imaging device such as a CCD, in which a defect address of the solid-state imaging device is written in a nonvolatile memory provided in the solid-state imaging device. Regarding the method. [Summary of the Invention] The present invention provides a solid-state imaging device including a solid-state imaging device with a non-volatile memory and an input terminal for inputting data to be written into the non-volatile memory, detects the address of a defective part of the non-volatile memory, and inputs the data. By writing to the nonvolatile memory through the terminal, defects in the solid-state image sensor can be reliably corrected electrically.

[Conventional technology]

In a solid-state imaging device (semiconductor imaging device) such as a CCD, if there is a crystal defect in a part of the semiconductor crystal, electric charges are likely to be generated in the defective part due to thermal causes. The dark current is larger than the area without. For this reason, the video signal obtained by imaging
Noise at a level higher than the white level is mixed in, making the reproduced image difficult to see. Furthermore, black noise due to crystal defects may be mixed into the video signal obtained by imaging. Therefore, conventionally, as disclosed in Japanese Patent Publication No. Sho 6 G-3 4 8 7 2, address data of a defective part of a solid-state image sensor, that is, data of its horizontal address and vertical address, are prepared in advance. By writing it in ROM, when sampling and holding the video signal obtained from the solid-state image sensor during imaging, the signal corresponding to the address of the defective part can be replaced with the previous signal, or the signals before and after it can be replaced. Replacement with an average signal is performed.

Also, as disclosed in the same publication, instead of writing the data of the address of the defective part of the solid-state image sensor into the \ROM as it is, the data of the address of the defective part of the solid-state image sensor is written at the reference point, that is, the first horizontal scanning line of the field of the solid-state image sensor. Data on the scanning start point and the distance on the horizontal scanning line between adjacent ones of one or more defective parts are also written in the ROM. By the way, conventionally, a defective address of a solid-state image sensor is detected at the semiconductor factory where it is manufactured, and the defective address is written into a ROM such as a fuse ROM or an EPROM, and the solid-state image sensor is transferred together with the corresponding ROM. The solid-state image sensor and R
The OM was designed to be incorporated into a solid-state imaging device.

[Problem to be solved by the invention]

In this way, the defective address of the solid-state image sensor is detected at the semiconductor factory where it was manufactured, and the defective address is transferred to the fuse ROM. ．． The data is written in a ROM such as EFROM, and the solid-state image sensor is sent together with the corresponding ROM to a solid-state image sensor assembly factory, where the cased image sensor and ROM are
When incorporating this into a solid-state imaging device, there were the following problems.

In other words, a large number of solid-state image sensors and ROMs are sent from semiconductor factories to assembly plants, so if the correspondence between solid-state image sensors and ROMs becomes unclear during the process, or if a ROM breaks, it is time to replace the solid-state image sensors and ROMs. The solid-state image sensor becomes unusable and has no choice but to be discarded.

In view of the above, the present invention proposes a defective address writing method for a solid-state imaging device that can reliably electrically correct defects in the solid-state imaging device.

[Means to solve the problem]

The present invention provides a solid-state imaging device including a solid-state imaging device (2), a non-volatile memory (5)' and the non-volatile memory (5).
), an input terminal T3 is provided for inputting data to be written to the solid-state image sensor (2), the address of the defective part of the solid-state image sensor (2) is detected, and the address data for the defective part is written to the nonvolatile memory (5) through the input terminal T3. This is what I did. [Operation] According to the present invention, the address of the defective portion of the solid-state image sensor (2) is detected, and the address data of the defective portion is written to the nonvolatile memory (5) through the input terminal T3. [Example] Hereinafter, an example of the present invention will be described in detail with reference to FIG. In FIG. 1, (1) shows the solid-state imaging device as a whole, and (2) shows the CC as the solid-state imaging device.
D (consisting of three CCDs for red, green, and blue signals or one COD for monaural signals), and employs, for example, an interline transfer method as the charge transfer method. This CCD (2) is supplied with horizontal and vertical transfer pulses and the like based on horizontal and vertical synchronization pulses from a timing signal generation circuit (IC) (7).

The imaging output from C O D (2) is supplied to a sample and hold circuit (3) where it is sampled and held.

This sample and hold circuit (3) is supplied with a sampling pulse from a timing signal generation circuit (7). The sample and hold output from the sample and hold circuit (4) is supplied to the signal processing circuit (4). The signal processing circuit (4) performs gain correction, composite signal processing, etc. on the sample and hold output, and outputs the composite video signal to the conventionally provided output terminal T4, as well as to the newly provided output terminal. A sample-and-hold signal with or without gain correction is output to T.

(5) is EEFROM (electronic erasable and programmable read-only memory) as a non-volatile memory, which is a conventional memory that stores various data. , here, it is shared for storing the defective address of C O D (2).

This R OM (5) is supplied with an address signal from the timing signal generation circuit (7) at the time of reading. Then, the readout output is the control circuit (
IC) (6), and defective address data therein is supplied to a timing signal generation circuit (7). The above is the configuration of the main parts of the solid-state imaging device (1). Next, a defective address detection circuit (8) provided outside the solid-state imaging device (1) will be explained.

C O D (2) Uniform light of various intensities (intensity O
The timing generation circuit (7) is transmitted through the video signal obtained from the output terminal T1 (including the light of Based on the horizontal and vertical synchronization pulses obtained from C O D (2
) to detect defective addresses. The data of the detected defective address and the data indicating the oddness or evenness of the field, or the reference point, that is, the scanning start point of the first horizontal scanning line of the field of CCD (2) and one or more following sequentially. Data on the distance on the horizontal scanning line between adjacent defective parts and data indicating whether the field is odd or even are sent to the solid-state imaging device (1) through a newly provided input terminal T3. and write to it.

Next, based on the data of the defective address written in R O M (5) in this way, C O D (
A method of correcting the video signal from 2) will be explained.

C O D (2) receives horizontal and vertical transfer pulses etc. from the timing signal generation circuit (7), and C O D
(2) outputs an imaging output according to the light irradiated, and the imaging output is supplied to a sample and hold circuit (3) where it is sampled and held. Then, the timing generation circuit (
7), the horizontal and vertical transfer pulses and whether the fields are odd or even, and the defective address (from R O M (5)) are determined.
The timing signal generation circuit (7) temporarily stops supplying the sampling signal to the sample and hold circuit (3). For example, to hold previously sampled data. below,
This operation is repeated as many times as C O D (2).

Note that the defective address detection circuit (8) is connected to the solid-state imaging device (1).
) can be attached to it, but when it is not needed,
It shall be removed from the solid-state imaging device (1). According to the method for writing a defective address of a solid-state image sensor described above, the solid-state image sensor (1) including the solid-state image sensor (2)
), the non-volatile memory (5) and the non-volatile memory (
5) is provided with an input terminal T3 for inputting data to be written,
The address of the defective part is detected and written to the nonvolatile memory (5) through its input terminal T3.
Unlike conventional methods, there is no risk that the correspondence between the solid-state image sensor (2) and the non-volatile memory (5) in which the defective address has been written will be lost, or that the non-volatile memory (5) will be destroyed. , defects in the solid-state image sensor (2) can be reliably corrected electrically. [Effects of the Invention] According to the present invention described above, a solid-state imaging device including a solid-state imaging device is provided with a non-volatile memory and an input terminal for inputting data to be written into the non-volatile memory, and the address of a defective portion thereof is detected. Since the data is written to the nonvolatile memory through the input terminal, defects in the solid-state image sensor can be reliably corrected electrically.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of a solid-state imaging device to which the present invention is applied. (1) is a solid-state image sensor, (2) is a solid-state image sensor (COD)
), (3) is a sample hold circuit, (4) is a signal processing circuit, (5) is a non-volatile memory (ROM), (6) is a control circuit, (7) is a timing signal generation circuit,
(8) is a defective address detection circuit.

Claims (1)

[Claims] A solid-state imaging device including a solid-state imaging device is provided with a non-volatile memory and an input terminal for inputting data to be written into the non-volatile memory, and the address of a defective portion of the solid-state imaging device is detected and the defect is detected. A method for writing a defective address in a solid-state imaging device, characterized in that address data of a part is written into the nonvolatile memory through the input terminal.