Abstract: A HDR CTIA pixel which provides automatic gain selection, and spatial and temporal coherence. The pixel comprises an input node for connection to a photocurrent, and an output node. The pixel includes a CTIA which comprises a “high gain” integration capacitor and a first reset switch connected between the input and output nodes, a “low gain” integration capacitor connected between the input node and a first node, a second reset switch connected between the first node and the output node, and a first FET connected across the second reset switch. In operation, the first FET is off during the reset phase, and is conditionally turned on during or after the integration phase. The CTIA also includes an amplifier having an inverting input connected to the input node and an output connected to the output node. The pixel can be operated in “static low-gain control” and “dynamic low-gain control” modes.

Abstract: A pixel comprising a pinned photodiode (PPD) which generates a photocurrent Iph, a transfer gate connected in series between the PPD and a first node, a low-gain select transistor connected between the first node and a second node, a reset transistor connected between the second node and a reset voltage, a capacitance connected between the second node and a first constant potential, and a source-follower transistor whose source, gate and drain are connected to an output node, the first node and a second constant potential, respectively. When properly arranged, a vertically integrated (3D) global-shutter pinned PPD pixel is provided, which uses an overflow integration capacitor and subthreshold conduction of the reset transistor for increased dynamic range. Global shutter operation is achieved by storing the pixel output on sampling capacitors in another semiconductor layer at the end of integration.

Abstract: A pixel comprising a pinned photodiode (PPD) which generates a photocurrent Iph, a transfer gate connected in series between the PPD and a first node, a low-gain select transistor connected between the first node and a second node, a reset transistor connected between the second node and a reset voltage, a capacitance connected between the second node and a first constant potential, and a source-follower transistor whose source, gate and drain are connected to an output node, the first node and a second constant potential, respectively. When properly arranged, a vertically integrated (3D) global-shutter pinned PPD pixel is provided, which uses an overflow integration capacitor and subthreshold conduction of the reset transistor for increased dynamic range. Global shutter operation is achieved by storing the pixel output on sampling capacitors in another semiconductor layer at the end of integration.

Abstract: A HDR CTIA pixel which provides automatic gain selection, and spatial and temporal coherence. The pixel comprises an input node for connection to a photocurrent, and an output node. The pixel includes a CTIA which comprises a “high gain” integration capacitor and a first reset switch connected between the input and output nodes, a “low gain” integration capacitor connected between the input node and a first node, a second reset switch connected between the first node and the output node, and a first FET connected across the second reset switch. In operation, the first FET is off during the reset phase, and is conditionally turned on during or after the integration phase. The CTIA also includes an amplifier having an inverting input connected to the input node and an output connected to the output node. The pixel can be operated in “static low-gain control” and “dynamic low-gain control” modes.

Abstract: An imaging system implementing a scheme for enhancing the dynamic range of the device. An array of radiation detecting pixels produces an output in response to a stimulus. The signal from each pixel is read once for evaluation. If the voltage at an individual pixel satisfies a programmed condition, such as exceeding a predetermined threshold voltage at a particular time, that pixel is reset and begins producing an output signal anew. If the pixel output signal does not satisfy the condition, it is allowed to continue producing the signal without being reset. After the evaluation read, all of the pixels are then read row by row into a buffer and digitally processed. A memory register tracks which pixels have been reset, and the corresponding output signals are adjusted accordingly. This scheme allows the system to process input signals across a broader range of intensity without losing information due to pixel saturation or sacrificing sensitivity.

Abstract: An imaging system implementing a scheme for enhancing the dynamic range of the device. An array of radiation detecting pixels produces an output in response to a stimulus. The signal from each pixel is read once for evaluation. If the voltage at an individual pixel satisfies a programmed condition, such as exceeding a predetermined threshold voltage at a particular time, that pixel is reset and begins producing an output signal anew. If the pixel output signal does not satisfy the condition, it is allowed to continue producing the signal without being reset. After the evaluation read, all of the pixels are then read row by row into a buffer and digitally processed. A memory register tracks which pixels have been reset, and the corresponding output signals are adjusted accordingly. This scheme allows the system to process input signals across a broader range of intensity without losing information due to pixel saturation or sacrificing sensitivity.