Chip circuit of image processing equipment, signal processing method and vehicle

Abstract

The embodiment of the invention provides a chip circuit of image processing equipment, a signal processing method and a vehicle, and the chip circuit comprises a first circuit which is used for generating a pixel signal, a second circuit which is used for generating a ramp signal, and a third circuit which is connected with the first circuit and the second circuit. The third circuit is used for generating image data based on the pixel signal generated by the first circuit and the ramp signal generated by the second circuit, and the second circuit comprises a ramp generation sub-circuit and a source follower sub-circuit connected with the output end of the ramp generation sub-circuit. According to the embodiment of the invention, the source follower sub-circuit introduces the non-linear gain to the ramp signal, and the non-linear gain and the non-linear gain of the pixel signal in the first circuit form common-mode interference, so that the influence of the non-linear gain introduced by the pixel unit source follower along with the change of the illumination condition can be counteracted, and the linearity of the image sensor system is improved; and the quantization error of the comparator under different illumination conditions is reduced.

Description

Technical Field

[0001] The present invention relates to the field of image data technology, and in particular to a chip circuit of an image processing device, a signal processing method and a vehicle. Background Art

[0002] When an existing image sensor chip collects pixel voltage signals, a source follower exists in the pixel unit. The source follower introduces nonlinear gain at the output end during operation, increases the quantization error of the comparator, and affects the imaging effect of the image sensor. Summary of the invention

[0003] In view of the above problems, a chip circuit, a signal processing method and a vehicle of an image processing device are proposed to overcome the above problems or at least partially solve the above problems, including:

[0004] A chip circuit of an image processing device, the chip circuit comprising: a first circuit for generating a pixel signal, a second circuit for generating a ramp signal, a third circuit connected to the first circuit and the second circuit, the third circuit being used to generate image data based on the pixel signal generated by the first circuit and the ramp signal generated by the second circuit, the second circuit comprising a ramp generating subcircuit and a source follower subcircuit connected to the output end of the ramp generating subcircuit.

[0005] Optionally, the source follower sub-circuit comprises: a source follower element, wherein a gate terminal of the source follower element is connected to an output terminal of the ramp generating sub-circuit.

[0006] Optionally, the source follower sub-circuit further includes: a power supply and a load resistor, the source terminal of the source follower element is connected to the load resistor, and the drain terminal of the source follower element is connected to the power supply.

[0007] Optionally, the load resistor is grounded at a side away from the source terminal.

[0008] Optionally, the third circuit includes a comparator element, a first end of the comparator element is used to receive a pixel signal input by the first circuit, a second end of the comparator element is used to receive a ramp signal input by the second circuit, and a third end of the comparator element is used to output quantized data generated by comparing the pixel signal and the ramp signal.

[0009] Optionally, when the first end of the comparator element is a non-inverting input end, the second end of the comparator element is an inverting input end, and when the second end of the comparator element is a non-inverting input end, the first end of the comparator element is an inverting input end;

[0010] Optionally, the third circuit includes a first switch control connected to the output end of the first circuit, and a second switch control connected to the output end of the first circuit and the output end of the second circuit, and the first switch control and the second switch control are used to control the pixel signal and the ramp signal to be input into the comparator element in a time-sharing manner.

[0011] Optionally, the source follower sub-circuit also includes a transistor between the source terminal and the drain terminal, the ramp signal includes a ramp voltage, and the source follower sub-circuit is used to control the source terminal and the drain terminal to be turned on after the ramp voltage is input into the gate terminal when the ramp voltage is greater than or equal to a threshold voltage.

[0012] Optionally, the source follower sub-circuit is used to control the source terminal and the drain terminal to be in a cut-off state when the ramp voltage is less than a threshold voltage.

[0013] Optionally, the source follower sub-circuit is used to output a ramp signal after gain processing by the source follower sub-circuit based on the power supply and the load voltage when the source terminal and the drain terminal are in a conductive state.

[0014] Optionally, the third circuit includes a comparator element, a first end of the comparator element is used to receive a pixel signal input by the first circuit, a second end of the comparator element is used to receive a ramp signal input by the second circuit, and a third end of the comparator element is used to output quantized data generated by comparing the pixel signal and the ramp signal.

[0015] Optionally, when the first end of the comparator element is the non-inverting input end, the second end of the comparator element is the inverting input end; when the second end of the comparator element is the non-inverting input end, the first end of the comparator element is the inverting input end.

[0016] Optionally, the third circuit includes a first switch control connected to the output end of the first circuit, and a second switch control connected to the output end of the first circuit and the output end of the second circuit, and the first switch control and the second switch control are used to control the pixel signal and the ramp signal to be input into the comparator element in a time-sharing manner.

[0017] Optionally, the state of the first switch control is the same as that of the third switch control, and the state of the first switch control is opposite to that of the second switch control.

[0018] Optionally, the first switch control and the third switch control have the same state, and the first switch control and the second switch control have opposite states, specifically including:

[0019] When the first switch control is in a closed state, the second switch control is in an open state, and the third switch control is in a closed state.

[0020] Optionally, the first switch control and the third switch control have the same state, and the first switch control and the second switch control have opposite states, specifically including:

[0021] When the first switch control is in an open state, the second switch control is in a closed state, and the third switch control is in an open state.

[0022] Optionally, the first switch control is controlled to be in a closed state and the second switch control is controlled to be in an open state within a preset first time period, so that the pixel signal is input into the comparator element.

[0023] Optionally, the first switch control is controlled to be in an open state and the second switch control is controlled to be in a closed state within a preset second time period, so that the ramp signal is input into the comparator element.

[0024] Optionally, the first end of the first switch control is connected to the output end of the first circuit, the first end of the second switch control is connected to the output end of the second circuit, and the second end of the first switch control is connected to the second end of the second switch control at a first node.

[0025] Optionally, the non-inverting input terminal and the inverting input terminal of the comparator element are set as the second node, the first end circuit of the second node is connected to the inverting input terminal of the comparator element, and the second end circuit of the second node is connected to the non-inverting input terminal of the comparator element.

[0026] Optionally, the third circuit further includes a third switch control, wherein the third switch control is located between the second node and the output terminal of the comparator element.

[0027] Optionally, the third circuit further includes a capacitive element between the first node and the second node.

[0028] Optionally, the third circuit further comprises a counter element connected to the output terminal of the comparator element, the counter element being used to generate image data based on the quantized data.

[0029] A signal processing method is applied to a chip circuit of an image processing device, the method comprising:

[0030] Acquiring a pixel signal and an initial ramp signal collected by the image processing device;

[0031] Using a source follower element in the chip circuit to perform signal processing on the initial ramp signal to obtain a target ramp signal;

[0032] Image data is generated based on the pixel signal and the target ramp signal.

[0033] A vehicle comprises the chip circuit as described above.

[0034] In an embodiment of the present invention, a chip circuit of an image processing device is provided, the chip circuit of the image processing device includes a first circuit for generating a pixel signal, a second circuit for generating a ramp signal, a third circuit connected to the first circuit and the second circuit, the third circuit is used to generate image data based on the pixel signal generated by the first circuit and the ramp signal generated by the second circuit, and the second circuit includes a ramp generating subcircuit and a source follower subcircuit connected to the output end of the ramp generating subcircuit. Thus, a nonlinear gain can be introduced into the ramp signal through the source follower subcircuit, forming a common mode interference with the nonlinear gain of the pixel signal in the first circuit, and the influence of the nonlinear gain introduced by the pixel unit source follower changing with the illumination condition can be offset, thereby improving the linearity of the image sensor system and reducing the quantization error of the comparator under different illumination conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solution of the present invention, the accompanying drawings required for use in the description of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0036] Figure 1 It is a pixel unit circuit in the prior art;

[0037] Figure 2a is a schematic structural diagram of a chip circuit of an image processing device provided by an embodiment of the present invention;

[0038] Figure 2b is a schematic structural diagram of a source follower sub-circuit provided by an embodiment of the present invention;

[0039] Figure 2c is a structural schematic diagram of a third circuit provided by an embodiment of the present invention;

[0040] Figure 2d is a structural schematic diagram of an image processing device provided by an embodiment of the present invention;

[0041] Figure 3 It is a flowchart of another signal processing method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0042] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] The main function of image sensors is to collect digital images and convert the collected light signals into electrical signals. At present, the image sensors used on a large scale are mainly divided into two types: CCD (Charge-Coupled Device) and CMOS (Complementary Metal-Oxide-Semiconductor). Compared with CCD image sensors, CMOS image sensors have the advantages of low power consumption, low cost and high compatibility, and are widely used in aerospace, biotechnology and consumer electronics.

[0044] As the scope of application expands, consumers have higher requirements for image size, and the demand for large-scale image sensors is increasing. When existing image sensor chips collect pixel voltage signals, they use the following methods: Figure 1 As an example, the pixel unit 4T structure shown in the figure has a source follower M5 in the pixel unit. The source follower M5 receives a signal at the gate and drives a load at the source. During its operation, a nonlinear gain A is introduced at the output end. v .

[0045]

[0046] The pixel voltage input to the comparator here introduces a nonlinear gain, while the ramp voltage input to the other end of the comparator does not have a nonlinear gain, thereby increasing the quantization error of the comparator and affecting the imaging effect of the image sensor. However, the prior art pays little attention to the nonlinear gain error introduced by the pixel unit structure. The comparator input has unequal gain nonlinearity and the influence of gain nonlinearity cannot be offset, resulting in a certain error between the actual quantization result of the comparator and the theoretical value.

[0047] In an embodiment of the present invention, the chip circuit of the image processing device can set a source follower sub-circuit on the ramp signal generating end to generate a nonlinear gain for the ramp signal, thereby causing the nonlinear gain and the nonlinear gain of the pixel signal to form a common-mode interference, thereby offsetting the influence of the nonlinear gain introduced by the pixel unit source follower as the lighting conditions change, thereby improving the linearity of the image sensor system and reducing the quantization error of the comparator under different lighting conditions.

[0048] Reference Figure 2a, showing a schematic structural diagram of a chip circuit of an image processing device provided by an embodiment of the present invention, the chip circuit includes: a first circuit 101 for generating a pixel signal, a second circuit 102 for generating a ramp signal, a third circuit 103 connected to the first circuit 101 and the second circuit 102, the third circuit 103 is used to generate image data based on the pixel signal generated by the first circuit 101 and the ramp signal generated by the second circuit 102, the second circuit 102 includes a ramp generating sub-circuit 11 and a source follower sub-circuit 12 connected to the output end of the ramp generating sub-circuit.

[0049] In practical applications, a photodiode is provided in the image processing device, and the photodiode can be used to collect the light signal. After the photodiode collects the light signal, the first circuit 101 can convert the light signal into an electrical signal to obtain a pixel signal. An active follower element is provided in the first circuit, so that the generated pixel signal carries a nonlinear gain.

[0050] The second circuit 102 can be used to generate an initial ramp signal and process the initial ramp signal, which is a reference signal for comparison with the pixel signal. The second circuit 102 may include a ramp generation subcircuit 11 and a source follower subcircuit 12, wherein the ramp generation subcircuit 11 is used to generate the initial ramp signal, and the source follower subcircuit 12 is used to process the initial ramp signal to obtain a target ramp signal, the target ramp signal may carry a nonlinear gain, and the nonlinear gain in the target ramp signal may be offset by the nonlinear gain carried by the pixel signal, thereby improving the accuracy of signal processing.

[0051] In one embodiment of the present invention, the source follower sub-circuit may include a source follower element, the gate end of the source follower element is connected to the output end of the ramp generating sub-circuit, the source follower element can be used to receive an initial ramp signal output by the ramp generating sub-circuit, and process the initial ramp signal to obtain a target ramp signal. The target ramp signal can carry a nonlinear gain, and the nonlinear gain in the target ramp signal can offset the nonlinear gain carried by the pixel signal, thereby improving the accuracy of signal processing.

[0052] In one embodiment of the present invention, the source follower subcircuit may further include: a power supply and a load resistor, the source terminal of the source follower element is connected to the load resistor, and the drain terminal of the source follower element is connected to the power supply. The power supply is used to provide an operating voltage for the source follower element (MOSFET). The source follower element acts as an amplifier element, the gate receives an input signal (i.e., an initial ramp signal), the source outputs a signal (i.e., a target ramp signal), and the load resistor is used to provide a load for the source follower subcircuit. One end of the load resistor can be connected to the source terminal and grounded on the side away from the source terminal.

[0053] In one embodiment of the present invention, the ramp signal includes a ramp voltage, and the source follower sub-circuit is used to control the source terminal and the drain terminal to be turned on when the ramp voltage is greater than or equal to the threshold voltage after the ramp voltage is input to the gate terminal; the source follower sub-circuit is used to control the source terminal and the drain terminal to be in a cut-off state when the ramp voltage is less than the threshold voltage.

[0054] The source follower sub-circuit can be used to output a ramp signal after gain processing by the source follower sub-circuit based on the power supply and load voltage when the source terminal and the drain terminal are in the on state.

[0055] In practical applications, the basic working principle of the source follower element is:

[0056] Input Signal: The input signal of the source follower is applied to the gate (G) of the MOSFET.

[0057] Output signal: The output signal is taken from the source (S) of the MOSFET and drives the load.

[0058] Following characteristics: Source voltage V S will "follow" the gate voltage V G , but usually there is a fixed voltage difference V GS , that is, V S =V G -V GS .

[0059] The source follower element has the characteristics of high input impedance, low output impedance and voltage following, among which: high input impedance means that the gate current of MOSFET is very small, and the source follower has a very high input impedance, which makes the source follower very suitable for use as a buffer or impedance converter.

[0060] Low output impedance means that the output impedance of the source is low, making it easier to drive the load.

[0061] Voltage following means that the source voltage follows the gate voltage, but there is a fixed voltage difference V GS .

[0062] Reference Figure 2b , shows a schematic diagram of the structure of a source follower subcircuit in an embodiment of the present invention, wherein the source follower subcircuit includes a source follower element 121, a power supply 122 and a load resistor 123, and the source follower element 121 may include a gate terminal 21, a source terminal 22 and a drain terminal 23. The gate terminal 21 is connected to the output terminal of the ramp generating subcircuit 11, and receives the initial ramp signal (i.e., V_ramp0) generated by the ramp generating subcircuit 11, the source terminal 23 of the source follower element 121 is connected to the load resistor 123, the drain terminal 23 of the source follower element 121 is connected to the power supply 122, and one end of the load resistor 123 is grounded.

[0063] After the initial ramp signal is processed by the source follower sub-circuit, a target ramp signal (i.e., V_ramp) is output. The target ramp signal contains the nonlinear gain generated by the source follower element. The target ramp signal is input into the third circuit for comparison with the pixel signal. Since both the pixel signal and the ramp signal contain nonlinear gain, common-mode interference can be formed between the pixel signal and the ramp signal, thereby offsetting the influence of the nonlinear gain introduced by the pixel unit source follower on changes in lighting conditions, thereby improving the linearity of the image sensor system and reducing the quantization error of the comparator under different lighting conditions.

[0064] In practical applications, the source follower receives a signal at the gate and drives a load at the source, so that the source potential can "follow" the voltage.

[0065] Analyze the large signal characteristics, when V_ramp0 <V TH When the initial ramp voltage is greater than the threshold voltage, M1 is in the cut-off state and V_ramp is equal to zero. As V_ramp0 increases and exceeds V TH , M1 turns on and enters the saturation region, I D1 (Current after conduction) flows through the resistor R s As V_ramp0 increases further, the output voltage V_ramp follows the input voltage V_ramp0, and the difference between the two (level shift) is V GS Ignoring the channel length modulation effect, the input-output characteristics can be expressed as:

[0066] Among them, I D1 .Rs=V_ramp,I D1 is the current associated with V_ramp0.

[0067]

[0068] Differentiating V_ramp0 on both sides of the above equation, we can get the small signal gain of the circuit:

[0069]

[0070] At the same time, use the chain rule:

[0071]

[0072] so

[0073]

[0074] Also because

[0075]

[0076] so

[0077]

[0078] When V_ramp0≈V TH (At this time g m ≈0), the gain increases monotonically from zero. m Get bigger, A v (Gain) Approx. Therefore, considering the body effect (i.e. g mb ), the source follower element has nonlinear gain in the saturation region.

[0079] In one embodiment of the present invention, the third circuit includes a comparator element, a first end of the comparator element is used to receive a pixel signal input by the first circuit, a second end of the comparator element is used to receive a ramp signal input by the second circuit, and a third end of the comparator element is used to output quantized data generated by comparing the pixel signal and the ramp signal.

[0080] In practical applications, the main function of the comparator element is to compare the pixel signal (analog signal) with the ramp signal (reference signal). When the voltage of the pixel signal exceeds the voltage of the ramp signal, the comparator outputs a high level, otherwise it outputs a low level. The output of the comparator element is an analog signal, which can be used to represent the relative voltage size of the pixel signal and the ramp signal.

[0081] In one embodiment of the present invention, the comparator element may include an inverting input terminal, a non-inverting input terminal and an output terminal. When the first terminal of the comparator element is the non-inverting input terminal, the second terminal of the comparator element is the inverting input terminal. When the second terminal of the comparator element is the non-inverting input terminal, the first terminal of the comparator element is the inverting input terminal. That is, one of the two signals, the pixel signal and the target ramp signal, generated in the embodiment of the present invention is input into the comparator element through the inverting input terminal, and the other signal is input into the comparator element through the non-inverting input terminal.

[0082] In one embodiment of the present invention, the third circuit includes a first switch control connected to the output end of the first circuit, and a second switch control connected to the output end of the first circuit and the output end of the second circuit. The first switch control and the second switch control are used to control the time-sharing input of the pixel signal and the ramp signal into the comparator element.

[0083] Specifically, the first switch control is controlled to be in a closed state and the second switch control is controlled to be in an open state in a preset first time period, so that the pixel signal is input into the comparator element. The first switch control is controlled to be in an open state and the second switch control is controlled to be in a closed state in a preset second time period, so that the ramp signal is input into the comparator element.

[0084] In actual applications, when the first switch control is in a closed state, the pixel signal is input into the comparator element; when the first switch control is in an open state, the pixel signal stops being input into the comparator element; when the second switch control is in a closed state, the target ramp signal is input into the comparator element; when the second switch control is in an open state, the target ramp signal stops being input into the comparator, thereby realizing time-sharing input of the pixel signal and the target ramp signal by controlling the opening or closing of the first switch control and the second switch control.

[0085] In one embodiment of the present invention, the first end of the first switch control is connected to the output end of the first circuit, the first end of the second switch control is connected to the output end of the second circuit, and the second end of the first switch control is connected to the second end of the second switch control at a first node.

[0086] In one embodiment of the present invention, the non-inverting input terminal and the inverting input terminal of the comparator element can also be set as the second node, the first end circuit of the second node is connected to the inverting input terminal of the comparator element, and the second end circuit of the second node is connected to the non-inverting input terminal of the comparator element.

[0087] In an embodiment of the present invention, the third circuit may further include a third switch control, and the third switch control is located between the second node and the output terminal of the comparator element.

[0088] In one embodiment of the present invention, the third circuit further includes a capacitor between the first node and the second node. The capacitor is used to sample the pixel voltage signal and the reset level signal of the comparator.

[0089] In one embodiment of the present invention, the third switch control is located between the second node and the output terminal of the comparator element. The third switch control is used to achieve automatic resetting of the comparator element.

[0090] In an embodiment of the present invention, the states of the first switch control and the third switch control are the same, and the states of the first switch control and the second switch control are opposite.

[0091] In practical applications, when the first switch control is in a closed state, the left plate of the capacitor element simultaneously samples the pixel voltage signal; when the first switch control is in an open state and the second switch control is in a closed state, the pixel signal is input to the same phase or opposite phase input terminal of the comparator element, and the target ramp signal is input to the opposite phase or same phase input terminal of the comparator element. When the second switch control is in an open state, the target ramp signal stops inputting the comparator. By controlling the opening or closing of the first switch control and the second switch control, the pixel signal and the target ramp signal can be input in a time-sharing manner.

[0092] Reference Figure 2c, shows a schematic diagram of the structure of a third circuit in an embodiment of the present invention, wherein the comparator circuit part includes four transmission gate switches for controlling the time-sharing input of the pixel signal and the ramp signal in the comparator module, which are represented by switches S1, S1′ and S2, S2′ in the circuit schematic, S1, S1′ are the first switch controls, S2, S2′ are the second switch controls, S3, S3′ are the third switch controls, and C1, C2 are capacitor elements. In the automatic zeroing stage, the left and right plates of the capacitors C1 and C2 at the input end of the comparator respectively sample the pixel voltage signal and the reset level signal of the comparator.

[0093] The first switch controls S1 and S1′ can be turned on and off at the same time, and the second switch controls S2 and S2′ can be turned on and off at the same time. The above four switches cooperate with each other to realize the time-sharing input of the pixel signal and the ramp signal in the comparator module. The third switch controls S3 and S3′ collect the output signal from the comparator output end as a reset signal. Among them, the states of the first switch control and the third switch control are the same, and the states of the first switch control and the second switch control are different.

[0094] The working circuit of the comparison process inputs the ramp signal V_ramp to the non-inverting input terminal of the comparator, and the pixel signal V_pixel to the inverting input terminal of the comparator. When the pixel signal V_pixel overlaps with the ramp signal V_ramp (that is, the voltages at the two input terminals of the comparator are equal), the comparator flips, and the pixel signal conversion quantization work is completed.

[0095] In an embodiment of the present invention, the third circuit further comprises a counter element connected to the output terminal of the comparator element, the counter element being used to generate the image data based on the quantized data.

[0096] In actual applications, the counter receives the output of the comparator and counts according to the output of the comparator. When the comparator outputs a high level, the counter increases the count value; when the comparator outputs a low level, the counter maintains the current count value.

[0097] The output of the counter is a digital count value, which represents the strength of the pixel signal. The larger the count value, the stronger the pixel signal.

[0098] In an image sensor, the combination of comparators and counters ultimately outputs a digital image data consisting of pixel values ​​and an image matrix. The intensity of each pixel is represented by the count value of the counter, which corresponds to the grayscale or color value of the pixel. The count values ​​of all pixels are combined to form a two-dimensional matrix that represents the digital representation of the entire image.

[0099] Reference Figure 2d, shows a schematic diagram of the structure of an image processing device in an embodiment of the present invention, the image processing device may include a pixel unit, a ramp generating circuit, a source follower, a comparator and a counter. The pixel unit is used to generate a pixel signal (V pixel ), the ramp generation circuit is used to generate the initial ramp signal (V ramp0 ), the source follower is used to input the initial ramp signal (V ramp0 ) is processed into the target ramp signal V ramp Then the pixel signal (V pixel ) and the target ramp signal V ramp The input comparator is used for comparison to obtain quantized data, and then a counter is used to obtain image data.

[0100] In the embodiment of the present invention, a source follower SF is added to the output end of the ramp generating circuit through a differential operational amplifier (comparator) and two sampling capacitors, so that the source follower gain inside the pixel unit is The source follower gain at the output of the ramp circuit The comparator in-phase and inverting input terminals show common-mode interference, and the transistor size is adjusted to meet That is, the influence of the nonlinear gain introduced by the pixel unit source follower changing with the illumination conditions can be offset, and the quantization error of the comparator under different illumination conditions can be reduced.

[0101] In an embodiment of the present invention, a chip circuit of an image processing device can introduce nonlinear gain to a ramp signal through a source follower sub-circuit, forming common-mode interference with the nonlinear gain of a pixel signal in a first circuit, thereby offsetting the influence of the nonlinear gain introduced by the pixel unit source follower as the lighting conditions change, thereby improving the linearity of the image sensor system and reducing the quantization error of the comparator under different lighting conditions.

[0102] Reference Figure 3 , shows a flowchart of a signal processing method provided by an embodiment of the present invention. The chip circuit applied to the image processing device may specifically include the following steps:

[0103] Step S301, acquiring a pixel signal and an initial ramp signal collected by an image processing device;

[0104] The image processing device is provided with a photodiode, which can be used to collect light signals and then convert the light signals into electrical signals to obtain pixel signals. The pixel signal processing circuit is provided with an active follower element, so that the generated pixel signal carries a nonlinear gain.

[0105] The ramp signal is a reference signal for comparison with the pixel signal.

[0106] Step S302, using a source follower element in the chip circuit to perform signal processing on the initial ramp signal to obtain a target ramp signal;

[0107] The source follower can be used to process the initial ramp signal to obtain a target ramp signal. The target ramp signal can carry a nonlinear gain, and the nonlinear gain in the target ramp signal can offset the nonlinear gain carried by the pixel signal, thereby improving the accuracy of signal processing.

[0108] Step S302: generating image data based on the pixel signal and the target ramp signal.

[0109] After the pixel signal and the target ramp signal are generated, a comparator element may be used to compare the pixel signal and the target ramp signal to obtain quantized data, which is then input into a counter to generate image data.

[0110] Among them, the chip circuit of the image processing device may include: a first circuit for generating a pixel signal, a second circuit for generating a ramp signal, and a third circuit connected to the first circuit and the second circuit, the third circuit being used to generate image data based on the pixel signal generated by the first circuit and the ramp signal generated by the second circuit, and the second circuit including a ramp generating subcircuit and a source follower subcircuit connected to the output end of the ramp generating subcircuit.

[0111] In an embodiment of the present invention, a pixel signal and an initial ramp signal collected by an image processing device are acquired; a source follower element in a chip circuit is used to perform signal processing on the initial ramp signal to obtain a target ramp signal; and image data is generated based on the pixel signal and the target ramp signal. Thus, the source follower element can introduce a nonlinear gain to the ramp signal, forming a common-mode interference with the nonlinear gain of the pixel signal in the first circuit, thereby offsetting the influence of the nonlinear gain introduced by the pixel unit source follower as the lighting conditions change, thereby improving the linearity of the image sensor system and reducing the quantization error of the comparator under different lighting conditions.

[0112] It should be noted that, for the sake of simplicity, the method embodiments are described as a series of action combinations, but those skilled in the art should be aware that the embodiments of the present invention are not limited by the order of the actions described, because according to the embodiments of the present invention, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily required by the embodiments of the present invention.

[0113] An embodiment of the present invention further provides a vehicle, which includes the chip circuit as described above or the electronic device as described above.

[0114] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0115] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0116] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0117] The chip circuit, signal processing method and vehicle of an image processing device provided are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A chip circuit of an image processing device, characterized in that: The chip circuit includes: a first circuit for generating a pixel signal, a second circuit for generating a ramp signal, and a third circuit connected to the first circuit and the second circuit, wherein the third circuit is used to generate image data based on the pixel signal generated by the first circuit and the ramp signal generated by the second circuit, and the second circuit includes a ramp generating sub-circuit and a source follower sub-circuit connected to the output end of the ramp generating sub-circuit.

2. The chip circuit according to claim 1, characterized in that: The source follower subcircuit includes: a source follower element, wherein a gate terminal of the source follower element is connected to an output terminal of the ramp generating subcircuit.

3. The chip circuit according to claim 2, characterized in that: The source follower subcircuit further includes: a power supply and a load resistor, the source terminal of the source follower element is connected to the load resistor, and the drain terminal of the source follower element is connected to the power supply.

4. The method according to claim 3, characterized in that The load resistor is grounded at a side away from the source terminal.

5. The chip circuit according to claim 4, characterized in that: The ramp signal includes a ramp voltage, and the source follower sub-circuit is used to control the source terminal and the drain terminal to be turned on when the ramp voltage is greater than or equal to a threshold voltage after the ramp voltage is input to the gate terminal.

6. The chip circuit according to claim 4, characterized in that: The source follower subcircuit is used to control the source terminal and the drain terminal to be in a cut-off state when the ramp voltage is less than a threshold voltage.

7. The chip circuit according to claim 5, characterized in that: The source follower sub-circuit is used for outputting a ramp signal after gain processing by the source follower sub-circuit based on the power supply and the load voltage when the source terminal and the drain terminal are in a conductive state.

8. The chip circuit according to claim 1, characterized in that: The third circuit includes a comparator element, a first end of the comparator element is used to receive a pixel signal input by the first circuit, a second end of the comparator element is used to receive a ramp signal input by the second circuit, and a third end of the comparator element is used to output quantized data generated by comparing the pixel signal and the ramp signal.

9. The chip circuit according to claim 8, characterized in that: When the first end of the comparator element is the non-inverting input end, the second end of the comparator element is the inverting input end; when the second end of the comparator element is the non-inverting input end, the first end of the comparator element is the inverting input end.

10. The chip circuit according to claim 8, characterized in that: The third circuit includes a first switch control connected to the output end of the first circuit, and a second switch control connected to the output end of the first circuit and the output end of the second circuit. The first switch control and the second switch control are used to control the pixel signal and the ramp signal to be input into the comparator element in a time-sharing manner.

11. The chip circuit according to claim 10, characterized in that: The first switch control has the same state as the third switch control, and the first switch control has an opposite state to the second switch control.

12. The chip circuit according to claim 11, characterized in that: The first switch control has the same state as the third switch control, and the first switch control has the opposite state to the second switch control, specifically including: When the first switch control is in a closed state, the second switch control is in an open state, and the third switch control is in a closed state.

13. The chip circuit according to claim 11, characterized in that: The first switch control has the same state as the third switch control, and the first switch control has the opposite state to the second switch control, specifically including: When the first switch control is in an open state, the second switch control is in a closed state, and the third switch control is in an open state.

14. The chip circuit according to claim 10, characterized in that: The first switch control is controlled to be in a closed state and the second switch control is controlled to be in an open state within a preset first time period, so that the pixel signal is input into the comparator element.

15. The chip circuit according to claim 10, characterized in that: The first switch control is controlled to be in an open state and the second switch control is controlled to be in a closed state within a preset second time period, so that the ramp signal is input into the comparator element.

16. The chip circuit according to claim 10, characterized in that: A first end of the first switch control is connected to an output end of the first circuit, a first end of the second switch control is connected to an output end of the second circuit, and a second end of the first switch control is connected to a second end of the second switch control at a first node.

17. The chip circuit according to claim 16, characterized in that: The non-inverting input terminal and the inverting input terminal of the comparator element are set as the second node, the first end circuit of the second node is connected to the inverting input terminal of the comparator element, and the second end circuit of the second node is connected to the non-inverting input terminal of the comparator element.

18. The chip circuit according to claim 17, characterized in that: The third circuit further includes a third switch control located between the second node and an output terminal of the comparator element.

19. The chip circuit according to claim 17, characterized in that: The third circuit also includes a capacitive element between the first node and the second node.

20. The chip circuit according to claim 1, characterized in that: The third circuit further comprises a counter element connected to an output terminal of the comparator element, the counter element being configured to generate image data based on the quantized data.

21. A signal processing method, characterized in that: A chip circuit applied to an image processing device, the method comprising: Acquiring a pixel signal and an initial ramp signal collected by the image processing device; Using a source follower element in the chip circuit to perform signal processing on the initial ramp signal to obtain a target ramp signal; Image data is generated based on the pixel signal and the target ramp signal.

22. A vehicle, characterized in that: The vehicle comprises the chip circuit according to claims 1 to 20.

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