Stmicroelectronics S.a.

Teledyne E2v Semiconductors Sas

Stmicroelectronics (crolles 2) Sas

Stmicroelectronics (grenoble 2) Sas

Stmicroelectronics (rousset) Sas

Allegro Dvt

Frédéric Barbier

Benoît Deschamps

François Roy

Yvon Cazaux

Frédéric Mayer

Stéphane Gesset

Laurent Simony

Frederic Lalanne

Pierre Fereyre

David Coulon

Bruno Diasparra

Alexandre Cellier

Sébastien Alaiwan

In an active pixel sensor comprising a photodiode Dp, a memory node MN and a readout node SN, the memory node being provided to contain the charge generated by the photodiode at the end of an integration period allowing an integration in global shutter mode and a correlated double sampling, it is envisaged to carry out, in each integration period, at least one transfer {circle around (2)} of charge from the photodiode to the memory node followed by clipping {circle around (3)} of the amount of charge contained in the memory node at an intermediate voltage tafter the start of the integration period but before a last transfer of charge {circle around (4)} to the memory node at the end of the integration period. The pixels are subsequently read out, row by row, by correlated double sampling CDS. The one or more intermediate transfers, with clipping, to the memory node during the integration period allow the dynamic range of the sensor to be extended to high levels of ambient light while retaining good sensitivity to low levels of ambient light.

Control method for an active pixel image sensor

In a sensor comprising active pixels including a photodiode PHD, a memory node MN and a read-out node SN, the memory node being provided to hold the charge generated by the photodiode at the end of an integration period enabling integration in global-shutter mode and a correlated double sampling read-out, provision is made for the charge-storage capacity of the memory node to be at least N times higher than the charge-storage capacity of the photodiode (N being an integer higher than or equal to 2) and provision is made to carry out, in each integration and read-out cycle, during the integration duration Tint(i), N transfers Tri, Tri, Triof charge from the photodiode to the memory node, the N transfers being equally distributed over the integration duration. The dynamic range of the sensor is improved under high light levels.

Method for controlling an active pixel image sensor

The invention concerns active-pixel electronic image sensors. The pixel comprises a photodiode (PH) designed in a semiconductor active layer () and maintained at a nil reference potential, and above the active layer an anti-blooming gate (G) adjacent on one side to the photodiode and on another side to an evacuation drain (). The sensor comprises means for applying to the anti-blooming gate, during most of the duration of integration, a blocking potential creating beneath the gate a potential barrier of a first height, and, during a series of brief pulses over the duration of integration, an anti-blooming potential creating a potential barrier of a second height, lower than the first. The fact of only applying the anti-blooming voltage during the brief pulses reduces the dark noise induced by tunneling effect by the electric field between gate and photodiode.

Image sensor with anti-blooming gate

The invention relates to a method for capturing an image in an image sensor with a matrix of rows and columns of active pixels, powered between a first power supply terminal at zero potential (Vss) and a second power supply terminal at a positive power supply potential (Vdd). Each pixel comprises a photodiode and a gate for transferring the photogenerated charges to a charge storage node. A negative potential (VNEG) is applied to the transfer gate by a charge pump during the charge integration time and it receives a transfer control signal (TRA) common to all the pixels during a transfer time window. The transfer or reset control signal successively comprises at least one first phase during which it goes from the negative potential (VNEG) to a positive transfer potential, a second phase during which it goes from the positive transfer potential to the zero potential supplied by the first power supply terminal, a third phase of finite duration during which it remains at the zero potential, and a fourth phase in which it goes back from the zero potential to the negative potential supplied by the charge pump. Going through the power supply potential limits the current demands in the charge pump which has to re-establish the negative potential VNEG at the end of the transfer.

Method for capturing an image with dark current reduction and low power consumption

The invention proposes a method for distributing a signal to each block Bof a series of N adjacent blocks of identical design in an electronic circuit. It proposes, in an identical fashion for each of the N blocks, placing a timing delay circuit MUX-DELon the path for conveying a signal Sfrom the input INcof the block to an internal electrical node Ndof the block for this signal S; providing for the timing delay circuit to supply N delayed signals corresponding to N different timing delays &#x394;f, . . . &#x394;f, . . . &#x394;fseparated by an increment of elementary duration &#x394;t that corresponds to the elementary delay &#x394;t for transit of a block introduced into a conductive line; and selecting the delayed signal corresponding to the applicable timing delay according to the block in question, by means of an index signal propagated through the N blocks, and which is incremented or decremented on passage through each block.

Method for synchronously distributing a digital signal over N identical adjacent blocks of an integrated circuit

An imaging device includes at least one photosite formed in a semiconducting substrate and fitted with a filtering device for filtering at least one undesired radiation. The filtering device is buried in the semiconducting substrate at a depth depending on the wavelength of the undesired radiation.

Imaging device with filtering of the infrared radiation

The invention concerns a test stream generator for generating a compressed video stream for testing a video decoder, the generator including: a context-aware pseudo-random generator () adapted to generate pseudo-random values of syntax elements based on decoding context data; a decoding process module (') adapted to process the syntax element values and to generate the decoding context data and binarization context data; and a binarizer module () adapted to encode the syntax element values based on the binarization context data in order to generate the compressed video stream.

Video stream generator

A device for controlling an image sensor including at least one photosensitive cell including a photodiode capable of discharging into a sense node via a first MOS transistor, the sense node being connected to the gate of a second MOS transistor having its source connected to a processing system. The device includes a bias circuit capable of increasing the voltage of the source during the discharge of the photodiode into the sense node.

Pinned photodiode CMOS image sensor with a low supply voltage

An image sensor having a number of pixel zones delimited by isolation trenches, each pixel zone including a photodiode; a transfer gate associated with each of the pixel zones and arranged to transfer charge from the photodiode to a sensing node; and a read circuit for reading a voltage at one of the sensing nodes, the read circuitry including a number of transistors of which at least one is positioned at least partially over a pixel zone of the pixel zones.

Compact image sensor arrangement with read circuitry over pixel zones

A method may include a cycle of reading a current pixel including connecting the capacitive node of the pixel to a capacitive node of a previous pixel already read, connecting the capacitive node of the current pixel and the capacitive node of a previous pixel to an output line, reading a first voltage of the capacitive node of the pixel through the output line, transferring charges from the accumulation node to the capacitive node of the pixel, reading a second voltage of the capacitive node of the pixel through the output line, and disconnecting the capacitive node from the capacitive node of a previous pixel, and a cycle of reading a next pixel. This cycle may include accumulating charges in the accumulation node of the next pixel while the capacitive node of the current pixel is connected to a capacitive node of a previous pixel.

Method of capturing an image with an image sensor

An imaging element includes a photosensor and a transfer transistor to transfer electrical charges from the photosensor to a charge accumulation node. A selector is configured to receive at least two logic selection signals and to supply an activation signal, which is a function of the selection signals, to a control terminal of the transfer transistor. The selector is configured to receive at least two selection signals, each having a positive voltage when it is at a logic value 1 and a negative voltage when it is a logic value 0, and to supply the activation signal having a negative voltage when the imaging element is not selected.

Image sensor with individually selectable imaging elements

A pixel circuit of an image sensor includes a sense node for storing a charge transferred from one or more photodiodes, a source follower transistor having its gate coupled to the sense node and its source node coupled to an output line of the pixel circuit via a read transistor, wherein a body contact of the source follower transistor is connected to the output line.

Image sensor pixel circuit

A method for controlling a pixel may include first and second photosites, each having a photodiode and a charge-transfer transistor, a read node, and an electronic read element, all of which are common to all the photosites. The method may include an accumulation of photogenerated charges in the photodiode of the first photosite during a first period, an accumulation of photogenerated charges in the photodiode of the second photosite during a second period shorter than the first period, a selection of the signal corresponding to the quantity of charges accumulated in the photodiode of a photosite having the highest unsaturated intensity or else a saturation signal, and a digitization of the selected signal.

Matrix imaging device comprising at least one set of photosites with multiple integration times

A method of analog to digital voltage conversion including: generating a quadratic signal based on an analog time varying reference signal; generating a ramp signal based on the quadratic signal; and converting an analog input voltage to a digital output value based on a time duration determined by a comparison of the analog input voltage with the ramp signal.

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Grenoble, France

Frédéric Barbier