Major Types of Noise in Image Sensors - Essential Principles of Image Sensors - page 45

the time difference is very short for 1/f noise to change the level. Then, 1/f noise can be
removed by the same operation as CDS as well as reset noise.
Readers might have noticed that both the clamping and sampling operations cause kTC
noise. That is correct. But, fortunately, the signal after CDS operation can be treated as
a voltage signal, not as a charge quantity signal. As shown in Equation 3.8, the voltage
amplitude of kTC noise is inversely proportional to √ C , thus the noise amplitude problem
can be avoided by employing larger capacitors.
References
1. J.E. Carnes, W.F. Kosonocky, Noise source in charge-coupled devices, RCA Review , 33, 327-343,
1972.
2. T. Obara, A. Yonezawa, A. Teramoto, R. Kuroda, S. Sugawa, T. Ohmi, Extraction of time con-
stants ratio over nine orders of magnitude for understanding random telegraph noise in metal-
oxide-semiconductor field-effect transistors, Japanese Journal of Applied Physics , 53, 04EC19,
2014.
3. R. Kuroda, A. Yonezawa, A. Teramoto, T.-L. Li, Y. Tochigi, S. Sugawa, A statistical evaluation
of random telegraph noise of in-pixel source follower equivalent surface and buried-channel
transistors, IEEE Transactions on Electron Devices , 60(10), 3555-3561, 2013.