33 results about "Correlated double sampling" patented technology

Techniques and apparatuses are described that implement random modulation of charge-pump noise phases to reduce structured noise induced by the charge pump. In an example aspect, a correlated double sampling (CDS) circuit is coupled to a pixel array including at least one pixel circuit. The CDS circuit receives an input signal generated by the at least one pixel circuit from the pixel array and samples a reset component of the input signal during a first sampling time to generate a reset component sample. The first sampling time is at a first offset from a reset control signal and prior to a settling time of the at least one pixel circuit. The CDS circuit samples a signal component of the input signal during a second sampling time to generate a signal component sample and determines an output signal based on the reset component sample and the signal component sample.

The invention relates to a low-noise small-size active pixel circuit and a working method thereof, the low-noise small-size active pixel circuit comprises a charge transfer circuit, an overflow circuit and a signal readout circuit, the overflow circuit, the charge transfer circuit and the signal readout circuit are connected in sequence, the charge transfer circuit is used for completing charge-to-voltage conversion, the overflow circuit prevents saturated charge from overflowing, and the signal readout circuit is used for reading out signals. And the signal reading circuit is used for completing correlated double sampling and transmitting a signal to a next-stage circuit. According to the invention, an overflow pipe is added in an 8T circuit in the prior art, and charge overflow and adjacent pixel crosstalk under a strong light condition can be effectively inhibited by constructing a controllable charge discharge channel; a row selection transistor is omitted, signal reading is achieved through voltage control, and charging and discharging of a sampling capacitor are controlled by changing a time sequence.

An image sensor includes a pixel configured to operate in a high conversion gain mode and a low conversion gain mode during a readout period, and a correlated double sampling circuit configured to generate a comparison signal based on a ramp signal and a pixel voltage received from the pixel. The correlated double sampling circuit includes a comparator configured to receive the pixel voltage through a first input node, receive the ramp signal through a second input node based on receiving a low conversion gain reset signal or a low conversion gain image signal as the pixel voltage, and receive the ramp signal through a third input node based on receiving a high conversion gain reset signal or a high conversion gain image signal as the pixel voltage, and compare the ramp signal with the pixel voltage and output a comparison signal corresponding to a comparison result.

The invention provides a short wave infrared pixel readout circuit and a control method thereof, the short wave infrared pixel readout circuit converts an optical signal into a light current based on a photoelectric conversion module, and provides a preset transconductance gain through a symmetric differential amplification structure in a charge integration amplification module, so as to amplify the light current based on the preset transconductance gain; charge integration is carried out on the light current to obtain integral voltage; and performing reset sampling and signal sampling on the integral voltage through the correlated double-sampling module to obtain a sampling voltage. The short-wave infrared pixel reading circuit provided by the invention adopts a symmetrical differential amplification input structure, has a relatively high common-mode rejection ratio and a relatively good anti-interference capability, and improves the anti-interference capability in an amplification process under the condition of not increasing power consumption; the correlated double sampling modules are concentrated in the reading circuit, signals are not transmitted for multiple times between pixels and a column-level circuit, the processing pressure of the column-level circuit is reduced, the number of circuit switches is small, time sequence control is simple, and the pixel area is reduced.

An image sensor includes: a pixel configured to operate in a high conversion gain mode and a low conversion gain mode during a readout period, and sequentially output a low conversion gain reset signal, a high conversion gain reset signal, a high conversion gain image signal, and a low conversion gain image signal as pixel voltages; a correlated double sampling circuit configured to compare the ramp signal with a pixel voltage received from the pixel and generate a comparison signal; and a counter circuit configured to generate a high conversion gain pixel value and a low conversion gain pixel value based on a comparison signal and a count code received from the correlated double sampling circuit, the count code having a code value that increases over time.

The application provides a resistance temperature sensor and a test method and a measurement method and a power switch system, which comprises a Wheatstone bridge, a driving stage circuit comprising a first driving circuit and a second driving circuit, two excitation ends connected to the Wheatstone bridge respectively, an analog-to-digital converter with a first input end and a second input end connected to two output voltage ends of the Wheatstone bridge respectively, one output end serving as an output end of the temperature sensor, a driving controller with an output end connected to the first driving circuit and the second driving circuit respectively and also connected to the analog-to-digital converter, and a sampling period comprising two measurement stages in sequence, the first driving circuit enabled in the first measurement stage and the second driving circuit enabled in the second measurement stage. The analog-to-digital converter is used to execute its working time sequence in sequence in a sampling period, quantize two measurement results respectively, and subtract the two quantization results to obtain an output result. The technical scheme of the application adopts correlated double sampling, and improves the precision of the measurement result.

The invention relates to the technical field of infrared imaging, in particular to a low-power-consumption infrared reading circuit based on a phase inverter and a control method, and the low-power-consumption infrared reading circuit comprises a capacitance trans-impedance amplifier based on the phase inverter, a correlated double-sampling circuit based on the phase inverter and an analog-to-digital converter, the capacitor trans-impedance amplifier based on the phase inverter comprises a first transistor, a second transistor, a third transistor, a fourth transistor, a first capacitor and a first diode, and the correlated double-sampling circuit based on the phase inverter comprises a first sampling switch, a second sampling switch, a second capacitor, a third capacitor and a differential amplifier based on the phase inverter. By adopting the capacitor trans-impedance amplifier based on the phase inverter and a double-sampling circuit structure and utilizing the current multiplexing characteristic of the phase inverter, the problem that an infrared reading circuit is high in power consumption and difficult to deploy in an edge end low-power-consumption scene in the prior art is solved, and the power consumption of the circuit is remarkably reduced.

The invention provides a pixel reading circuit and a control method thereof, and the pixel reading circuit comprises a photoelectric conversion module, a gain adjustment module, a correlated double sampling module, a gain control feedback module and an output module. The gain adjusting module is used for carrying out integral processing on the light current signal to obtain integral voltage, the correlated double sampling module is used for sampling the integral voltage to obtain effective signal voltage, and the gain control feedback module is used for generating a gain control signal based on the effective signal voltage so as to adjust integral gain. And the output module buffers and outputs the effective signal voltage. According to the circuit provided by the invention, the correlated double sampling function is integrated in the pixel, the number of used switches is small, time sequence control is simple, the pixel area is reduced, the chip integration degree is high, multiple times of transmission of signals between the pixel and the column-level circuit is avoided, the processing pressure of the column-level circuit is relieved, and the system frame rate is improved.

This invention discloses an image processing circuit for autonomous vehicles, belonging to the field of image processing technology. It solves the problems of unexpected refraction and scattering of light due to physical defects in optical microlenses and color filters, and charge coupling caused by parasitic capacitance in pixel units, leading to leakage of optical / electrical signals from a single pixel to adjacent pixels, resulting in color aliasing and blurred image edges. The circuit includes a main image sensor module, a reference image sensor module, and an analog signal preprocessing and multiplexing module. This invention coordinates the synchronous signal acquisition of the main and reference image sensors through a low-jitter clock distribution module. After integration by the analog signal preprocessing module, a dynamic crosstalk compensation module generates an inverse compensation signal based on the reference signal. A high-precision differential correlation dual sampling module then performs noise suppression and crosstalk elimination on the main signal. Finally, a programmable gain amplifier module outputs the purified differential signal.

The invention relates to a low-noise time quantization circuit suitable for a laser radar focal plane detector, and belongs to the technical field of reading circuits of laser radar focal plane detectors. Compared with a traditional TAC architecture, the TAC architecture is based on a correlated double sampling principle, utilizes noise correlation between a reset signal and an effective signal in the same pixel readout circuit, caches a reset voltage and an effective signal voltage by using a pre-storage circuit in the pixel readout unit, and reads the reset voltage and the effective signal voltage to the correlated double sampling circuit through a column bus for subtraction; the influence of 1 / f noise, KCT noise, array fixed mode noise and other noise is greatly reduced, and the signal-to-noise ratio of focal plane imaging is improved.

The invention discloses a voltage signal acquisition module for a quantum precision measurement device. The voltage signal acquisition module comprises seven parts, namely a weak voltage signal, a correlated double-sampling differential input circuit, a front-end analog signal amplifying and conditioning circuit, a high-precision ADC analog-to-digital conversion circuit, a digital control and signal processing unit, an embedded display control screen and a linear isolation voltage-stabilized power supply. The invention also discloses a sampling method. Target voltage signals and circuit voltage noise are effectively separated through the correlated double-sampling differential input circuit, weak voltage signal extraction is achieved, and the key technical problem of weak voltage signal collection in a quantum precision measurement device is effectively solved through the integrated design of hardware optimization and software processing.

The invention discloses a counter circuit and an image sensor, and belongs to the field of integrated circuit design, a counter module in the counter circuit can perform quantization of each stage according to a reading time sequence of double conversion gains, after a low conversion gain reset code is obtained through quantization, the low conversion gain reset code can be latched to a first latch unit, and a second latch unit is latched to a second latch unit; and after the correlation double sampling result of the high conversion gain is quantized and latched to the second latch unit, the low conversion gain reset code in the first latch unit can be read back, the negation value of the low conversion gain reset code is used as an initial count value, the low conversion gain signal level is counted, and the low conversion gain signal level is calculated. Therefore, the counter circuit suitable for the image sensor in the dual-conversion gain mode is realized through the single counter module, only a single data transmission channel is needed, the number of devices of the counter circuit is reduced, and the area of the circuit is reduced.

A touch detection method, a touch chip (1) and an electronic device. The touch detection method comprises: applying a driving signal encoded based on a preset encoding mode to a driving channel (TX1, TX2, TX3, TX4) of a touch screen; wherein the encoding mode comprises: dividing a plurality of signal waveforms of the driving signal into waveforms of at least one correlated double sampling period, and the same correlated double sampling period contains two sampling periods (101) with a phase difference of 180° between the waveforms; receiving a sensing signal (102) corresponding to the driving signal from a sensing channel (RX1, RX2, RX3, RX4) of the touch screen; and determining touch position information (103) according to the sensing signal and the encoding information corresponding to the encoding mode. The technical solution can improve the ability to resist low-frequency interference in touch detection, thereby improving the signal-to-noise ratio of the system and enhancing the touch sensitivity.

A method for processing an analogue signal is provided. An example includes a method for processing an analogue signal from a pixel using a correlated double sampling method including two successive measurements of durations between the instant of start of a ramp signal and the instant where the pixel signal crosses the ramp. A single counting circuit is used for the two measurements and in particular a single counter that will provide the two counting values used for generating the least significant bits of the output digital word representative of the amount of light captured by the pixel.

An image sensor has a three device layers. Through substrate MIM (TSMIM) capacitors are disposed in the middle device layer. The TSMIM capacitors may replace capacitors that would otherwise be disposed in the metal interconnect structure of the second device layer allowing that metal interconnect structure, particularly the uppermost metallization layer, to be thinner. Thinning that upper metallization layer reduces parasitic capacitance and increases dynamic range. The TSMIM capacitors may be correlated double sampling (CDS) capacitors, lateral overflow integration capacitors (LOFICs), or any other type of capacitor used in a photodetector circuit.

The application discloses a correlated double sampling circuit, comprising a signal sampling circuit and a signal output circuit; wherein the signal sampling circuit samples signals of reset stage and integration stage of a previous stage circuit by controlling on and off of a switch, realizes subtraction operation of reset signals and integration signals by using the characteristic that electric charges on a capacitor cannot be suddenly changed, and eliminates low-frequency noise, KTC noise and FPN noise in the output signal of the previous stage circuit; the signal output circuit outputs the effective signal after noise reduction through a circuit composed of a ground switch, a reference voltage switch and a capacitor, and outputs the effective signal by using the characteristic that electric charges on the capacitor cannot be suddenly changed. The circuit realizes the functions of noise reduction of the correlated double sampling circuit and accurate output of the effective signal after noise reduction, improves the signal-to-noise ratio of the output signal, and can also simplify the circuit, reduce power consumption, area and noise of the whole circuit.

The application discloses a correlated double sampling successive approximation analog-to-digital converter and a conversion method thereof. The analog-to-digital converter comprises a shift register, a comparator, a positive-phase conversion capacitor array and a negative-phase conversion capacitor array; the positive-phase conversion capacitor array and the negative-phase conversion capacitor array receive a reference voltage, an input voltage and a reset voltage through a reference voltage interface, a signal voltage interface and a reset voltage interface respectively for signal processing, and output a voltage signal to the comparator; a positive-phase input end of the comparator is connected with the positive-phase conversion capacitor array, a negative-phase input end is connected with the negative-phase conversion capacitor array, and an output is connected with the shift register; voltage signals of the positive-phase conversion capacitor array and the negative-phase conversion capacitor array are received by the positive-phase input end and the negative-phase input end respectively for comparison, and valid bit data is output and stored to the shift register. By adopting a single-end signal input and a maximum capacitor bridging structure, the overall area and power consumption of an image sensor readout circuit can be reduced.

The invention discloses an infrared detector pixel unit and a control method thereof. A signal saturation clamping circuit is adopted, and image dithering caused by nonlinear change of an integrating capacitor during signal saturation can be solved by designing a reasonable clamping voltage; a high-linearity NMOS (N-channel Metal Oxide Semiconductor) source follower is adopted, the VTH nonlinear change introduced by a substrate bias effect is solved through an auxiliary source follower, and substrate interference is avoided, so that the pixel linearity is improved to 1 per thousand magnitude in a large signal processing range; a row gating circuit with a crosstalk suppression function is adopted, and in the design of a large-array infrared detector, crosstalk generated through column line Kick-back during adjacent row reading is reduced during snapshot exposure row-by-row reading; the method is suitable for realizing a correlated double-sampling function of infrared pixel signals through an analog-to-digital converter.

According to the digital sampler circuit provided by the embodiment of the invention, the modulation circuit and the correlated double sampling circuit are arranged in the digital sampler circuit, and the modulation circuit is used for switching and connecting the output end and the grounding end of the signal source based on the first pulse signal; the method comprises the following steps of: switching a received level signal between an effective level and a zero level of a signal source, respectively latching the effective level and the zero level by using a correlated double-sampling technology, and outputting a difference value between the effective level and the zero level, so that the effect of deducting error electromotive force from the effective level is realized, and the accuracy of the error electromotive force is improved. The influence of error electromotive force caused by noise signals on the effective level of a signal source is reduced, and the signal-to-noise ratio of the digital sampler circuit is improved, so that the accuracy of a chip test result is improved.

The application provides a low-noise high-linearity capacitive humidity sensor MEMS conditioning chip circuit and a detection method, and belongs to the technical field of CMOS integrated circuits.The circuit comprises a calibration enhanced correlated double sampling capacitive voltage converter, a low-pass filter and a sigma-delta ADC with a MASH 2-2 structure;an input end of the calibration enhanced correlated double sampling capacitive voltage converter is connected with a sensing element, the sensing element comprises a variable capacitor Cs and a reference capacitor C0;an input end of the low-pass filter is connected with an output end of the calibration enhanced correlated double sampling capacitive voltage converter; and an input end of the sigma-delta ADC with the MASH 2-2 structure is connected with an output end of the low-pass filter.The application realizes single-chip integration of humidity signal reading and processing and a front-end reading circuit, has an extremely low input noise base, an extremely high linearity, a lower power consumption and an enhanced calibration function, and is suitable for humidity detection in complex environments.

A Correlated Double Sampling (CDS) integrating circuit and a data converter, the CDS circuit includes a CDS integration module and a level shifting module. The CDS integration module is configured to sample a first input signal and an Operational Amplifier (Opamp) input offset voltage to a sampling capacitor during a first phase; and sample a second input signal and the Opamp input offset voltage to the sampling capacitor during a second phase, and transfer a charge difference generated on the sampling capacitor to an integrating capacitor. The level shifting module is configured to sample an output signal and a common-mode voltage to a level shifting capacitor during a first stage of the first phase and the second phase, and shift a potential of an Opamp output voltage towards the common-mode voltage through the level shifting capacitor in a second stage of the second phase.

The application provides an infrared detection method based on scene signal hierarchical self-enhancement, which integrates a regulation strategy model under different thermal radiation background conditions, an optimal bias mapping model under different scenes and a scene classifier model into a readout circuit hierarchical self-enhancement model; the captured scene signal is analyzed to extract a pixel level interest unit signal and a non-interest unit signal, the collected scene signal is input into the readout circuit hierarchical self-enhancement model, and optimal bias parameters, optimal control voltages, optimal integration time and integration capacitance values are calculated; the optimal bias parameters are used to drive a pixel array to obtain an original infrared image, the original infrared image is subjected to signal hierarchical self-enhancement according to the obtained control parameters, and finally, relevant double sampling is performed to obtain high-quality infrared image signal output. The application improves the temperature resolution of the image in the interest region.

The process for processing an analog signal from a pixel uses a method called correlated double sampling, which involves two successive measurements of the time between the start of a ramp signal and the moment the pixel signal crosses the ramp. A single counting circuit (CCPT) is used for both measurements, and in particular a single counter (CPT1) which provides the two count values ​​used to generate the least significant bits of the output digital word representing the amount of light captured by the pixel. (See Figure 3 for abbreviations.)

The application provides a driving method of a pixel array, an image sensor and an electronic device. In the driving method of the pixel array, a row selection signal is first output row by row for row-by-row quantization, and a first clamping control signal is provided to a row selection transistor corresponding to a preset clamping row in the pixel array when the row selection signal is provided to the row selection transistor of the quantized row. When a light problem causes the signal output transistor to be in a preset state, for example, the output current is too small or the transistor is turned off, each row selection transistor corresponding to the preset clamping row is triggered to be turned on and clamps the connected output line to a first preset voltage, and a current branch is generated. The current branches of the reset readout period and the exposure readout period are the same, so that the current difference can be eliminated by correlated double sampling, the imaging consistency of the pixel array is improved, and the image contrast and the image quality are improved.

The invention discloses a photodiode full well capacity testing method based on digital correlation double sampling and a medium. The photodiode full-well capacity testing method is used for testing the photodiode full-well capacity of an image sensor, and comprises the following steps: extracting a corresponding first illumination value when FD reaches a saturation output state, a photodiode does not reach an actual full-well state and a light response curve saturation code value reaches; extracting a second illumination value when the photodiode reaches an actual full well state and the saturation code value of the light response curve starts to drop; and calculating the actual full well capacity of the photodiode according to the saturation code value of the light response curve, the first illumination value and the second illumination value in combination with the conversion gain of the sensor. According to the invention, the actual full well capacity of the photodiode can be measured without changing the structure and the time sequence.

The application relates to a programmable gain amplifier circuit for extending the dynamic range of an image sensor, comprising a switched capacitor circuit and a negative feedback DC offset cancellation circuit; the switched capacitor circuit is used for twice correlated double sampling and amplification processing of the output signal of the image sensor pixel column, eliminating the fixed pattern noise and reset thermal noise, and outputting high-sensitivity and low-sensitivity analog voltages; the negative feedback DC offset cancellation circuit is used for reducing the influence of the offset voltage of the main operational amplifier on the output voltage by adopting an operational amplifier offset voltage storage mode. In the application, the image column fixed pattern noise caused by the offset voltage of the main operational amplifier can be greatly reduced through the operational amplifier offset storage technology, and the high-sensitivity and low-sensitivity analog signal inputs can be provided for the post-processing circuit in time through the twice correlated double sampling processing technology, so that the dynamic range of the image sensor is extended, and the image imaging quality is improved.

The invention provides a Hall sensor, a chip and electronic equipment, and relates to the technical field of integrated circuits. The Hall sensor is characterized in that a clock generation circuit generates a correction magnetic field control signal to control the correction magnetic field generation circuit to generate a correction magnetic field, and the clock generation circuit generates a phase control clock signal to control a four-phase rotating Hall circuit to generate four initial Hall signals with different phases under the modulation of the correction magnetic field; the initial Hall signal of each phase is amplified by the front-end voltage amplification circuit and then is sent to the correlated double-sampling demodulation circuit for sampling demodulation so as to obtain a Hall voltage signal. The initial Hall signal of each phase comprises a corresponding Hall voltage signal, an offset voltage signal and a voltage signal of a correction magnetic field, the size of the Hall voltage signal of each phase is unchanged, the polarity of the Hall voltage signal of each phase is alternately changed, and in each four phases, the polarity of the voltage signal of the correction magnetic field of each phase is alternately changed. According to the scheme, the delay of the signal link can be reduced, and the rate of the signal link can be improved.

An artificial prosthesis is disclosed, which comprises a pixel array, a correlated double sampling unit, an analog-to-digital converter, a digital core, and a digital-to-analog converter. The digital core is configured to perform a calculation of electrical stimulation waveform of each of the pixels by using a processing function of an ANN. As such, the neural stimulation levels for artificial vision can be optimized.

The invention discloses an optical communication O-band high-transmittance quantum dot infrared detector and a preparation method, the detector comprises a photoelectric detection unit, the photoelectric detection unit comprises a PCB (101), a board-level circuit area (102) and a pixel electrode (103), the board-level circuit area (102) and the pixel electrode (103) are arranged on the PCB (101), the board-level circuit area (102) and the pixel electrode (103) are connected through lead bonding, and the PCB (101) and the pixel electrode (103) are connected through lead bonding. Noise suppression and signal conversion read-out are realized through integral signal read-out and correlated double sampling circuit design; and the quantum dot device unit comprises an annular pixel region (104) which is arranged on the silicon wafer substrate (106) and completes functional layer deposition and a hollow part (105) of the annular pixel region (104). The quantum dot material is based on the characteristic that the band gap of the PbS colloidal quantum dot is continuously adjustable, accurate matching of spectral response of a detector can be achieved by simply adjusting synthesis parameters of the quantum dot and the size of an annular pixel of the detector, the solution method processing characteristic of the quantum dot is high in process compatibility, and an efficient technical path is provided for subsequent product iteration.

First and second modulation gates disposed adjacent a silicon photoconversion structure generate, throughout the exposure interval, alternating first and second electrostatic fields that compel photocharge generated within the silicon photoconversion structure to the first and second storage diodes, respectively. Upon conclusion of the exposure interval, accumulated photocharge within the first and second storage diodes is transferred to first and second floating diffusion nodes, respectively, as part of a correlated-double-sampling readout with respect to each of the floating diffusion nodes.