Design of a CMOS x-ray line scan sensors

Citation

Heo, C.-W., Jang, J.-H., Jinliyan, Heo, S.-K., Kim, T.-W., Ha, P.-B., & Kim, Y.-H.. (2013). Design of a CMOS x-ray line scan sensors. Journal of the Korea Institute of Information and Communication Engineering, 17(10), 2369–2379. https://doi.org/10.6109/jkiice.2013.17.10.2369

Keywords

• CMOS x-ray line scan sensor
• DC-DC converter
• Binning
• Fully differential image signal
• Pixel circuit
• Image resolution modes
• Indirect detection
• Power supply noise
• Input common mode noise
• SHA (Sample-and-Hold Amplifier)

Brief

This article presents the design of a CMOS x-ray line scan sensor that uses a newly proposed pixel circuit to support three binning modes (no binning, 2x2 binning, and 4x4 binning) for adjustable pixel size and outputs a fully differential image signal to reduce noise sensitivity.

Summary

This article presents a design for a CMOS x-ray line scan sensor, intended for use in both medical imaging and non-destructive testing. The sensor features a 512 column × 4 row pixel array and incorporates a DC-DC converter. The design allows for the selection of different pixel sizes (100㎛, 200㎛, and 400㎛) through the utilization of no binning, 2×2 binning, and 4×4 binning modes. The sensor outputs a fully differential image signal, making it resilient to power supply and input common mode noise.

The article highlights that conventional x-ray line scan sensors are susceptible to various noise sources due to their single-ended image signal output. The newly designed sensor aims to overcome this limitation by employing a fully differential signal output. The design, implemented using a 0.18㎛ x-ray CMOS image sensor process, occupies a layout area of 51,304㎛ × 5,945㎛. It's also mentioned that the sensor can be tiled to create larger line scan sensor systems.

Origin: https://citeseerx.ist.psu.edu/document?repid=rep1&type=pdf&doi=a5af7db7cc168d7a906b1a3c68534e3b622b4d07