An Area-Efficient Readout Circuit for a High-SNR Triple-Gain LOFIC CMOS Image Sensor †
Abstract
1. Introduction
- To mitigate the SNR drop, we propose the triple-gain LOFIC CIS without enlarging the pixel area or degrading motion artifacts.
- We propose a readout circuit that is area-efficient for the triple-gain LOFIC CIS.
- We evaluate a fabricated test chip and estimate the SNR.
Updates from the Conference Proceeding
- Pixel- and circuit-gain combination for the MCG signal (Section 2.1, Figure 1).
- Details of the baseline circuit and comparison with the proposed readout circuit (Section 3.1, Figure 3).
- Noise analysis of baseline circuit and proposed readout circuit (Figure 4 and Figure 6).
- A discussion of this study and a comparison with other works (Section 4).
2. Concept-Level Design
2.1. Pixel- and Circuit-Gain Combination for the MCG Signal
2.2. Voltage-Level Diagram
3. Proposed Readout Circuit for a Triple-Gain LOFIC CIS
3.1. Baseline Readout Circuit
3.2. Proposed Circuit
4. Fabrication and Evaluation of a Test Chip
Discussion
5. Summary
Author Contributions
Funding
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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HCG | MCG | LCG | |
---|---|---|---|
Measured circuit gain [V/V] | |||
Estimated total gain [] | 771 | 103 |
HCG | MCG | LCG | |
---|---|---|---|
Measurement [] | |||
Estimation [] |
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Otani, A.; Ogawa, H.; Miyauchi, K.; Morikawa, Y.; Owada, H.; Takayanagi, I.; Okura, S. An Area-Efficient Readout Circuit for a High-SNR Triple-Gain LOFIC CMOS Image Sensor. Sensors 2025, 25, 6093. https://doi.org/10.3390/s25196093
Otani A, Ogawa H, Miyauchi K, Morikawa Y, Owada H, Takayanagi I, Okura S. An Area-Efficient Readout Circuit for a High-SNR Triple-Gain LOFIC CMOS Image Sensor. Sensors. 2025; 25(19):6093. https://doi.org/10.3390/s25196093
Chicago/Turabian StyleOtani, Ai, Hiroaki Ogawa, Ken Miyauchi, Yuki Morikawa, Hideki Owada, Isao Takayanagi, and Shunsuke Okura. 2025. "An Area-Efficient Readout Circuit for a High-SNR Triple-Gain LOFIC CMOS Image Sensor" Sensors 25, no. 19: 6093. https://doi.org/10.3390/s25196093
APA StyleOtani, A., Ogawa, H., Miyauchi, K., Morikawa, Y., Owada, H., Takayanagi, I., & Okura, S. (2025). An Area-Efficient Readout Circuit for a High-SNR Triple-Gain LOFIC CMOS Image Sensor. Sensors, 25(19), 6093. https://doi.org/10.3390/s25196093