US 11,310,454 B2 · Pixel circuit and image sensor having the same

Abstract

Provided are a pixel circuit and an associated image sensor, including an inverting input circuit, an active load and a signal reading circuit. Each pixel circuit includes a light sensing component, a transmission switch, a reset switch and a unity gain buffer. The transmission switch is series-connected between the light sensing component and the transmission switch. The unity gain buffer is connected to a node of connection of the transmission switch and the reset switch. The signal read circuit reads a sensing signal of the light sensing component through the unity gain buffer. An output signal of the unity gain buffer varies with an input signal of the unity gain buffer, attaining a linear relationship between the output signal and the input signal. Therefore, the photoelectric conversion curve of each pixel circuit is linear.

Claims20

Dependent claims

A pixel circuit, characterized by comprising:

a light sensing component;
a reset switch connected to a first reference voltage;
a transmission switch series-connected between the light sensing component and the reset switch;
and
a unity gain buffer comprising:
a non-inverting input circuit comprising a non-inverting input terminal connected to a node of connection of the transmission switch and the reset switch;
an inverting input circuit comprising an inverting input terminal;
and
an active load comprising an output terminal connected to the inverting input terminal, the active load being connected to the non-inverting input circuit and the inverting input circuit.

6 more elements

Dependencies are inferred from the claim text.

Facts

Application

16/706,374Filed 6 Dec 2019 · continuation

Priority

20 Nov 2018

Published

US 2020/0162690 A121 May 2020

Granted

19 Apr 2022

Term ends

Not estimatedThe source records don’t support an estimate.

Classification6 codes

H04N 25/77
Addressed sensors, e.g. MOS or CMOS sensors: pixel circuitry, e.g. memories, A/D converters, pixel amplifiers, shared circuits or shared components
H04N 25/778
Pixel circuitry, e.g. memories, A/D converters, pixel amplifiers, shared circuits or shared components: comprising amplifiers shared between a…
H10F 39/182
Complementary metal-oxide-semiconductor [CMOS] image sensors; Photodiode array image sensors: colour image sensors
H04N 25/78
Addressed sensors, e.g. MOS or CMOS sensors: readout circuits for addressed sensors, e.g. output amplifiers or A/D converters

Pixel circuit and image sensor having the same

Life of this patent

Pixel circuit and image sensor having the same

Life of this patent

Abstract

Claims20