Japanese Journal of Applied Physics publishes an open-access Sony paper "Noise reduction effect and analysis through serial multiple sampling in a CMOS image sensor with floating diffusion boost-driving" by Hayato Wakabayashi, Keiji Yamaguchi, and Yuuki Yamagata. Part of the material has been already published in other papers in the recent years.
"We have developed a 1/2.3-in. 10.3 mega pixel back-illuminated CMOS image sensor utilizing serial multiple sampling. This sensor achieves an RMS random noise of 1.3e- and row temporal noise (RTN) of 0.19e-. Serial multiple sampling is realized with a column inline averaging technique without the need for additional processing circuitry. Pixel readout is accomplished utilizing a 4-shared-pixel floating diffusion (FD) boost-driving architecture. RTN caused by column parallel readout was analyzed considering the transfer function at the system level and the developed model was verified by measurement data taken at each sampling time. This model demonstrates the RTN improvement of 1.6 dB in a parallel multiple readout architecture."