Patent ID: 8969775
Filing Date: 2015-03-03
Classification: H04N

Abstract:
1. A pixel cell for use in a high dynamic range image sensor, comprising: a photodiode disposed in semiconductor material to accumulate charge in response to light incident upon the photodiode; a transfer transistor disposed in the semiconductor material coupled between a floating diffusion and the photodiode; a first amplifier transistor disposed in the semiconductor material having a gate terminal coupled to the floating diffusion and a source terminal coupled to generate a first output signal of the pixel cell; and a second amplifier transistor disposed in the semiconductor material having a gate terminal coupled to the floating diffusion and a source terminal coupled to generate a second output signal of the pixel cell, wherein the first amplifier transistor has a first threshold voltage and a first gain, wherein the second amplifier transistor has a second threshold voltage and a second gain, wherein the first threshold voltage is different than the second threshold voltage and the first gain is different than the second gain such that the first and second amplifier transistors have different sensitivities to an intensity of the light incident on the photodiode.