Case Study of a Global Shutter CIS--Part 1: Angular Dependency of the Light Sensitivity

This article focuses on the angular dependency of the light sensitivity of a commercially available CMOS camera with a global shutter (storage node (SG) in the charge domain) and shared pixel architecture. The angular dependency is characterized as a function of both the wavelength and the angle of incidence of the incoming light. The...

An Offset Calibration Technique for CIS Column-Parallel SAR ADCs Using Memory

A column-parallel 10-bit SAR ADC for high-speed image sensors has been implemented. A fast offset calibration technique using memory is proposed to compensate for the offset mismatch, accompanied by an ADC designed for a narrow space the size of a single column pitch. The memory accumulates the variation of the offset to track the offset...

Case Study of a Global Shutter CIS--Part 2: Parasitic Light Sensitivity

This article focuses on the parasitic light sensitivity (PLS) of a commercially available CMOS camera with a global shutter (with a storage node in the charge domain) and shared pixel architecture. The PLS is characterized as a function of both the wavelength and the incident angle of the incoming light. The measurement results are linked to...

A Deep Sub-Electron Temporal Noise CMOS Image Sensor with Adjustable sinc-type Filter to Achieve Photon Counting Capability

This letter introduces a Gm-cell-based CMOS image sensor (CIS) achieving deep subelectron noise performance. The CIS presents a new compensation block and low-noise current source to improve the performance of the Gm pixel. Furthermore, an optional first-order IIR filter is implemented to improve the output swing. The conversion gain, full...

There's More to the Picture Than Meets the Eye*, and in the future it will only become more so

One of the fastest growing markets in the semiconductor industry is being driven by businesses in the solid-state imaging sector. An overview of the world-wide CIS (CMOS Image Sensor) market is illustrated in Figure 1.4.1. The actual CAGR (compound annual growth rate) from 2010 until 2019 was 15.2% in units and 16.9% in sales, while the...

In-Pixel temperature sensors with an accuracy of ±0.25 °C, a 3σ variation of ±0.7 °C in the spatial domain and a 3σ variation of ±1 °C in the temporal domain

This article presents in-pixel (of a CMOS image sensor (CIS) temperature sensors with improved accuracy in the spatial and the temporal domain. The goal of the temperature sensors is to be used to compensate for dark (current) fixed pattern noise (FPN) during the exposure of the CIS. The temperature sensors are based on substrate parasitic...

A CMOS Image Sensor with Thermal Sensing Capability and Column Zoom ADCs

This paper presents a CMOS image sensor (CIS) with a zoom ADC, to quantize in-pixel temperature sensors, as well as for faster readout speed of the image pixels while maintaining low quantization noise. The proposed 15 bit zoom ADC has a 4 bit Unit Capacitor Array (UCA) SAR and a 13 bit incremental 2^nd-order delta-sigma ADC (DSADC)...

A 10 bit 5 MS/s column SAR ADC with digital error correction for CMOS image sensors

This brief proposes a successive approximation register (SAR) analog-to-digital converter (ADC) whose readout speed is improved by 33%, through applying a digital error correction (DEC) method, compared to an alternative without using the DEC technique. The proposed addition-only DEC alleviates the ADC's incomplete settling errors, hence...

A CMOS-Imager-Pixel-Based Temperature Sensor for Dark Current Compensation

This brief proposes employing each of the classical 4 transistor (4T) pinned photodiode (PPD) CMOS image sensor (CIS) pixels, for both imaging and temperature measurement, intended for compensating the CISs' dark current, and dark signal non-uniformity (DSNU). The proposed temperature sensors rely on the thermal behavior of MOSFETs working in...

Suppression of spatial and temporal noise in a CMOS image sensor

This paper presents methodologies for suppressing the spatial and the temporal noise in a CMOS image sensor (CIS). First of all, it demonstrates by using a longer-length column bias transistor, both the fixed pattern noise (FPN) and temporal noise can be suppressed. Meantime, it employs column-level oversampling delta-sigma ADCs to suppress...

Compensation for Process and Temperature Dependency in a CMOS Image Sensor

This paper analyzes and compensates for process and temperature dependency among a (Complementary Metal Oxide Semiconductor) CMOS image sensor (CIS) array. Both the analysis and compensation are supported with experimental results on the CIS’s dark current, dark signal non-uniformity (DSNU), and conversion gain (CG). To model and to...

Temporal noise analysis of charge-domain sampling readout circuits for cmos image sensors

This paper presents a temporal noise analysis of charge-domain sampling readout circuits for Complementary Metal-Oxide Semiconductor (CMOS) image sensors. In order to address the trade-off between the low input-referred noise and high dynamic range, a Gm-cell-based pixel together with a charge-domain correlated-double sampling (CDS) technique...

Integration of 555 temperature sensors into a 64 × 192 CMOS image sensor

In this work, a novel approach for measuring relative temperature variations across the active area of a CMOS image sensor itself is presented. 555 Image pixels have been replaced by temperature sensors pixels (Tixels) in the same pixel array layer. Both sensors, pixels and Tixels, utilize the same readout structure to obtain the data. This...

A 0.5e_rms⁻ Temporal Noise CMOS Image Sensor With Gm-Cell-Based Pixel and Period-Controlled Variable Conversion Gain

A deep subelectron temporal noise CMOS image sensor (CIS) with a Gm-cell based pixel and a correlated-double charge-domain sampling technique has been developed for photon-starved imaging applications. With the proposed technique, the CIS, which is implemented in a standard 0.18-μm CIS process, features pixel-level amplification and achieves an...