[1] Lecture Notes, EE6350 VLSI Design Laboratory. Dr. Peter Kinget, Columbia University in the City of New York, Spring 2016.

[2] Alhawari, Mohammad et al. "A 0.5V < 4uW CMOS Light-to-Digital Converter Based on a Nonuniform Quantizer for a Photoplethysmographic Heart-Rate Sensor," IEEE Journal of Solid-State Circuits, vol. 49, no. 1, pp 271-88, 2014.

[3] Allen, John. "Photoplethysmography and Its Application in Clinical Physiological Measurement," Physiological Measurement 28.3, 2007.

[4] Allen, P. E., and Douglas R. Holberg. CMOS Analog Circuit Design, 2nd Edition. New York: Oxford UP, 2002.

[5] Wong, Alex et al. "A Low-Power CMOS Front-End for Photoplethysmographic Signal Acquisition With Robust DC Photocurrent Rejection," IEEE Transactions on Biomedical Circuits and Systems, vol. 2, no. 4, pp. 280-288, Dec. 2008.