Fast and low-power multiplexing circuit and use thereof in imaging devices

A pixel and readout circuitry therefor adapted for integration in an imaging device, comprising

• a radiation sensitive element able to produce an electrical signal indicative of the amount of radiation picked up by that pixel,
• a signal input node, a signal level being obtained from the radiation sensitive element,
• a first memory element for storing the signal level on the corresponding signal input node
• at least a first output node comprising a second memory element
• a first switching element being connected to the first memory element on one side and the first output node on the other side, and
• a second switching element to bring the first output node in a known state.

An array of pixels for integration in an imaging device, each pixel comprising a radiation sensitive element able to produce an electrical signal indicative of the amount of radiation picked up by that pixel, further comprising:

• a signal input node, a signal level being obtained from the radiation sensitive element,
• a first memory element for storing the signal level on the corresponding signal input node
• at least a first output node comprising a second memory element
• a first switching element being connected to the first memory element on one side and the first output node on the other side, and
• a second switching element to bring the first output node in a known state.

A method for reading out a solid state imaging device having a group of pixels, each pixel comprising a radiation sensitive element, the method comprising the following steps:

• reading out the signal of a pixel brought in a first state and storing the corresponding charge in a first memory element
• bring the output line into a reference state
• sharing the charge on the first memory element with a second memory element on an output line, and
• repeating these steps for at least part of the pixels of the imaging device.