CN112825548A - Method for reducing crosstalk of image sensor circuit - Google Patents
Method for reducing crosstalk of image sensor circuit Download PDFInfo
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- CN112825548A CN112825548A CN201911149437.0A CN201911149437A CN112825548A CN 112825548 A CN112825548 A CN 112825548A CN 201911149437 A CN201911149437 A CN 201911149437A CN 112825548 A CN112825548 A CN 112825548A
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- 239000003990 capacitor Substances 0.000 claims abstract description 33
- 230000000903 blocking effect Effects 0.000 claims abstract description 22
- 238000006243 chemical reaction Methods 0.000 claims abstract description 7
- 238000002347 injection Methods 0.000 claims description 4
- 239000007924 injection Substances 0.000 claims description 4
- 238000003384 imaging method Methods 0.000 abstract description 7
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N25/00—Circuitry of solid-state image sensors [SSIS]; Control thereof
- H04N25/60—Noise processing, e.g. detecting, correcting, reducing or removing noise
- H04N25/617—Noise processing, e.g. detecting, correcting, reducing or removing noise for reducing electromagnetic interference, e.g. clocking noise
Abstract
The invention provides a method for reducing crosstalk of an image sensor circuit, wherein an analog-digital conversion circuit of the image sensor comprises a plurality of rows of comparators; after the input offset is eliminated, incompletely same charges are respectively injected into high-resistance points of input blocking capacitors of different rows of comparators, so that the number of comparators which are turned over simultaneously in the rows of comparators is reduced, the crosstalk of a circuit is reduced, the signal stability and the imaging quality are improved, and the performance of an image sensor is improved.
Description
Technical Field
The invention relates to a realization method for reducing crosstalk of an image sensor circuit.
Background
With the continuous development of semiconductor technology, the design of high-pixel image sensors is more and more complex, and hundreds of comparators are often included in the analog-digital conversion circuit of the image sensor. During the operation of the image sensor, if the multiple columns of comparators are turned over at the same time, crosstalk will be formed between the comparators, which greatly reduces the signal stability and the imaging quality and affects the performance of the image sensor.
Disclosure of Invention
The invention aims to provide a realization method for reducing circuit crosstalk of an image sensor, which can improve signal stability and imaging quality and improve the performance of the image sensor.
Based on the above consideration, the present invention provides a method for reducing crosstalk in an image sensor circuit, wherein an analog-to-digital conversion circuit of the image sensor includes a plurality of rows of comparators; after the input offset is eliminated, incompletely same charges are injected into high-resistance points of input blocking capacitors of different rows of comparators respectively, so that the number of comparators which are turned over simultaneously in multiple rows of comparators is reduced, and crosstalk of a circuit is reduced.
Preferably, the charge injection is realized by adopting a differential capacitance mode at the high-resistance point of the input blocking capacitors of different column comparators.
Preferably, the charges of the multiple-column comparators which are not completely identical are N, and the multiple-column comparators are inverted at N time points; wherein N is a natural number of 2 or more.
Preferably, the high-resistance points of the input blocking capacitors at the two input ends of the comparator can be used for injecting charges.
Preferably, the number of columns of the multi-column comparator is 1000 or more.
The method for reducing the crosstalk of the image sensor circuit injects incompletely same charges at the high-resistance points of the input blocking capacitors of different rows of comparators, so that the number of comparators which are overturned simultaneously in the rows of comparators is reduced, the crosstalk of the circuit is reduced, the signal stability and the imaging quality are improved, and the performance of the image sensor is improved.
Drawings
Other features, objects and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments thereof, which proceeds with reference to the accompanying drawings.
FIG. 1 is a circuit diagram of an Mth column of comparators in an image sensor according to the present invention;
FIG. 2 is a schematic diagram of an injected charge configuration of different column comparators in accordance with a preferred embodiment of the present invention;
FIG. 3 is a schematic diagram of an injected charge configuration of different column comparators according to another preferred embodiment of the present invention;
FIG. 4 is a schematic diagram of an injected charge configuration of different column comparators according to another preferred embodiment of the present invention.
In the drawings, like or similar reference numbers indicate like or similar devices (modules) or steps throughout the different views.
Detailed Description
In order to solve the above problems in the prior art, the present invention provides a method for reducing crosstalk in an image sensor circuit, wherein an analog-to-digital conversion circuit of the image sensor includes a plurality of rows of comparators; after the input offset is eliminated, incompletely same charges are respectively injected into high-resistance points of input blocking capacitors of different rows of comparators, so that the number of comparators which are turned over simultaneously in the rows of comparators is reduced, the crosstalk of a circuit is reduced, the signal stability and the imaging quality are improved, and the performance of an image sensor is improved.
The illustrated embodiments are not intended to be exhaustive of all embodiments according to the invention. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.
The present invention will be described in detail with reference to specific examples.
The invention provides a method for reducing crosstalk of an image sensor circuit, wherein an analog-digital conversion circuit of the image sensor comprises a plurality of columns of comparators, for example, the number of columns of the plurality of columns of comparators can be more than or equal to 1000. Fig. 1 shows a schematic circuit diagram of an mth column comparator COMP-M, which has two input terminals Vin1, Vin2 corresponding to the input dc blocking capacitors C1, C2 and the high impedance points H1, H2, respectively, so that the input dc blocking capacitors C1 of the two input terminals Vin1, Vin2 and the high impedance points H1, H2 of C2 can be used to inject charges.
As an example, fig. 1 shows that the charge injection is implemented by using a differential capacitance method at the high-resistance point H2 of the input blocking capacitor C2 of one of the input terminals Vin 2. Specifically, as shown in fig. 1, at least two capacitors C3 and C4 are connected at a high impedance point H2 of an input blocking capacitor C2 of an mth column comparator COMP-M, the value of a total capacitance value C = C3+ C4 of the mth column comparator COMP-M is fixed and is the same for each column, wherein C3 is connected to a first external voltage Vext1 for injecting charges, C4 is connected to a second external voltage Vext2 as a compensation capacitor, Vext2 may be a ground voltage Vgnd, for example, the value of the capacitor C3 for injecting charges for controlling each column of comparators is not exactly the same, and correspondingly, the value of the compensation capacitor C4 for each column of comparators is not exactly the same. Of course, it is also possible to adopt no differential capacitance method, that is, only the capacitor C3 for injecting charges is connected at the high-resistance point H2 of the input blocking capacitor C2 without connecting the compensation capacitor C4, and the values of the capacitors C3 for injecting charges controlling each column of comparators are not completely the same. When the values of the capacitors C3 for injecting charges of each column of comparators are not identical, the injection of the non-identical charges Q at the high-resistance point H2 of the input blocking capacitor C2 can be easily realized regardless of whether the first external voltages Vext1 are identical or different.
In addition, as shown in fig. 1, the capacitor C3 for injecting charges can be switched between the first external voltage Vext1 and the pixel voltage Vpxda, so that, when the value of the capacitor C3 for injecting charges of each column of comparators is the same, the pixel voltage Vpxda can be sampled first and then the first external voltage Vext1 can be sampled, and since the value of the pixel voltage Vpxda of each column of comparators is not completely the same, it is only necessary to control the value of the voltage difference between the first external voltage Vext1 of each column of comparators and the pixel voltage Vpxda to be not completely the same, that is, the incompletely same charge Q can be injected at the high-resistance point H2 of the input blocking capacitor C2.
Fig. 2, fig. 3, and fig. 4 respectively show schematic diagrams of configurations of charges respectively injected at high-resistance points of input blocking capacitors of different column comparators after input offset cancellation is completed in different embodiments of the present invention. In a preferred embodiment shown in fig. 2, the injected charges Q at the high-impedance points of the input blocking capacitors of different column comparators are changed in a single parabolic shape, so that two column comparators M11, M12 with the same injected charges Q will be flipped simultaneously; in another preferred embodiment shown in fig. 3, the injected charges Q at the high-impedance points of the input blocking capacitors of different column comparators are changed in a periodic parabolic manner, and the six column comparators M21, M22, M23, M24, M25 and M26 with the same injected charges Q are simultaneously flipped; in another preferred embodiment shown in fig. 4, the injected charges Q at the high-impedance points of the input blocking capacitors of different column comparators vary randomly, and the four column comparators M31, M32, M33 and M34 with the same injected charges Q will be flipped simultaneously.
The skilled in the art can understand that the above configuration of injecting charges is only an example and not a limitation, in short, after the input offset cancellation is completed, incompletely identical charges are respectively injected at the high resistance points of the input blocking capacitors of different column comparators, and since the column comparators with the same injected charges are flipped at the same time, when the incompletely identical charges of the multiple column comparators are N, the multiple column comparators are flipped at N time points, where N is a natural number greater than or equal to 2, thereby reducing the number of the comparators flipped at the same time in the multiple column comparators, reducing crosstalk of the circuit, improving signal stability and imaging quality, and improving the performance of the image sensor.
In summary, in the implementation method for reducing the crosstalk of the image sensor circuit of the present invention, the analog-to-digital conversion circuit of the image sensor includes a plurality of rows of comparators; after the input offset is eliminated, incompletely same charges are respectively injected into high-resistance points of input blocking capacitors of different rows of comparators, so that the number of comparators which are turned over simultaneously in the rows of comparators is reduced, the crosstalk of a circuit is reduced, the signal stability and the imaging quality are improved, and the performance of an image sensor is improved.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive. Furthermore, it will be obvious that the word "comprising" does not exclude other elements or steps, and the word "a" or "an" does not exclude a plurality. Several elements recited in the apparatus claims may also be implemented by one element. The terms first, second, etc. are used to denote names, but not any particular order.
Claims (5)
1. An implementation method for reducing crosstalk of an image sensor circuit is characterized in that,
the analog-digital conversion circuit of the image sensor comprises a plurality of columns of comparators;
after the input offset is eliminated, incompletely same charges are injected into high-resistance points of input blocking capacitors of different rows of comparators respectively, so that the number of comparators which are turned over simultaneously in multiple rows of comparators is reduced, and crosstalk of a circuit is reduced.
2. The method of claim 1, wherein the charge injection is implemented by using differential capacitors at high impedance points of input blocking capacitors of different column comparators.
3. The method of claim 1, wherein the non-identical charges of the multi-column comparators are N, and the multi-column comparators are inverted at N time points; wherein N is a natural number of 2 or more.
4. The method of claim 1, wherein the input blocking capacitors at the two inputs of the comparator are both used to inject charges at a high impedance point.
5. The method of claim 1, wherein the number of columns of the multi-column comparator is greater than or equal to 1000.
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Citations (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004047087A (en) * | 2003-08-18 | 2004-02-12 | Pioneer Electronic Corp | Information recorder and information recording method |
| CN101677245A (en) * | 2008-09-17 | 2010-03-24 | 比亚迪股份有限公司 | Analog-digital converting circuit, analog-digital converting method and image processing system |
| US20100194951A1 (en) * | 2005-07-01 | 2010-08-05 | Commissariat A L'energie Atomique | Image sensing microelectronic device with asynchronous analog-to-digital converter |
| CN101867687A (en) * | 2009-04-14 | 2010-10-20 | 索尼公司 | Analog to digital converter, solid-state image sensing device and camera system |
| CN102983836A (en) * | 2012-11-27 | 2013-03-20 | 重庆西南集成电路设计有限责任公司 | Automatic frequency tuning circuit of active resistance-capacitance (RC) filter |
| CN103051289A (en) * | 2012-12-20 | 2013-04-17 | 清华大学深圳研究生院 | Preliminary amplifier with low clock crosstalk, dynamic comparator and circuit |
| US20130113461A1 (en) * | 2011-11-08 | 2013-05-09 | Texas Instruments Incorporated | Mitigating the effects of signal overload in analog front-end circuits used in image sensing systems |
| CN203117298U (en) * | 2013-01-30 | 2013-08-07 | 比亚迪股份有限公司 | Capacitance detection circuit |
| US20130201361A1 (en) * | 2012-02-06 | 2013-08-08 | Samsung Electronics Co., Ltd. | Image Sensor and Image Processing Apparatus Using the Same |
| CN103686004A (en) * | 2013-12-11 | 2014-03-26 | 格科微电子（上海）有限公司 | Column parallel analog-to-digital converter, pixel photosensitive value output method and CMOS image sensor |
| CN103714330A (en) * | 2014-01-06 | 2014-04-09 | 李扬渊 | Capacitive fingerprint sensor |
| CN105305961A (en) * | 2015-10-29 | 2016-02-03 | 上海华力微电子有限公司 | Oscillating circuit for eliminating comparator delay |
| CN106537595A (en) * | 2014-07-25 | 2017-03-22 | 索尼公司 | Solid-state image pickup element, AD converter, and electronic apparatus |
| CN107396009A (en) * | 2017-08-25 | 2017-11-24 | 电子科技大学 | Pulse frequency modulated type image sensor circuit and its processing method |
| CN107563361A (en) * | 2017-09-30 | 2018-01-09 | 苏州迈瑞微电子有限公司 | A kind of sensor pixel and optical sensor |
| CN107736015A (en) * | 2015-12-22 | 2018-02-23 | 索尼公司 | Imaging sensor, electronic equipment, control device, control method and program |
| CN108184081A (en) * | 2018-01-15 | 2018-06-19 | 北京时代民芯科技有限公司 | A kind of high-speed data reading circuit in cmos image sensor |
| CN110213513A (en) * | 2019-05-07 | 2019-09-06 | 天津大学 | A kind of high-speed figure correlated double sampling circuit structure based on monocline ADC |
-
2019
- 2019-11-21 CN CN201911149437.0A patent/CN112825548B/en active Active
Patent Citations (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004047087A (en) * | 2003-08-18 | 2004-02-12 | Pioneer Electronic Corp | Information recorder and information recording method |
| US20100194951A1 (en) * | 2005-07-01 | 2010-08-05 | Commissariat A L'energie Atomique | Image sensing microelectronic device with asynchronous analog-to-digital converter |
| CN101677245A (en) * | 2008-09-17 | 2010-03-24 | 比亚迪股份有限公司 | Analog-digital converting circuit, analog-digital converting method and image processing system |
| CN101867687A (en) * | 2009-04-14 | 2010-10-20 | 索尼公司 | Analog to digital converter, solid-state image sensing device and camera system |
| US20130113461A1 (en) * | 2011-11-08 | 2013-05-09 | Texas Instruments Incorporated | Mitigating the effects of signal overload in analog front-end circuits used in image sensing systems |
| US20130201361A1 (en) * | 2012-02-06 | 2013-08-08 | Samsung Electronics Co., Ltd. | Image Sensor and Image Processing Apparatus Using the Same |
| CN102983836A (en) * | 2012-11-27 | 2013-03-20 | 重庆西南集成电路设计有限责任公司 | Automatic frequency tuning circuit of active resistance-capacitance (RC) filter |
| CN103051289A (en) * | 2012-12-20 | 2013-04-17 | 清华大学深圳研究生院 | Preliminary amplifier with low clock crosstalk, dynamic comparator and circuit |
| CN203117298U (en) * | 2013-01-30 | 2013-08-07 | 比亚迪股份有限公司 | Capacitance detection circuit |
| CN103686004A (en) * | 2013-12-11 | 2014-03-26 | 格科微电子（上海）有限公司 | Column parallel analog-to-digital converter, pixel photosensitive value output method and CMOS image sensor |
| CN103714330A (en) * | 2014-01-06 | 2014-04-09 | 李扬渊 | Capacitive fingerprint sensor |
| CN106537595A (en) * | 2014-07-25 | 2017-03-22 | 索尼公司 | Solid-state image pickup element, AD converter, and electronic apparatus |
| CN105305961A (en) * | 2015-10-29 | 2016-02-03 | 上海华力微电子有限公司 | Oscillating circuit for eliminating comparator delay |
| CN107736015A (en) * | 2015-12-22 | 2018-02-23 | 索尼公司 | Imaging sensor, electronic equipment, control device, control method and program |
| CN107396009A (en) * | 2017-08-25 | 2017-11-24 | 电子科技大学 | Pulse frequency modulated type image sensor circuit and its processing method |
| CN107563361A (en) * | 2017-09-30 | 2018-01-09 | 苏州迈瑞微电子有限公司 | A kind of sensor pixel and optical sensor |
| CN108184081A (en) * | 2018-01-15 | 2018-06-19 | 北京时代民芯科技有限公司 | A kind of high-speed data reading circuit in cmos image sensor |
| CN110213513A (en) * | 2019-05-07 | 2019-09-06 | 天津大学 | A kind of high-speed figure correlated double sampling circuit structure based on monocline ADC |
Non-Patent Citations (3)
| Title |
|---|
| SEONG-JIN KIM: "A CMOS Image Sensor Based on Unified Pixel Architecture With Time-Division Multiplexing Scheme for Color and Depth Image Acquisition", 《IEEE JOURNAL OF SOLID-STATE CIRCUITS》 * |
| 邓准;谢亮;金湘亮;: "用于视频图像传感器的12 bit 60 MS/s流水线模数转换器", 太赫兹科学与电子信息学报, no. 06 * |
| 陈鸣: "一种应用于CMOS图像传感器的流水线模数转换器设计", 《吉林大学学报(工学版)》 * |
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