US 8,300,116 B2 · Two-path sigma-delta analog-to-digital converter and image sensor including the same

Abstract

A two-path sigma-delta analog-to-digital converter and an image sensor including the same are provided. The two-path sigma-delta analog-to-digital converter includes at least one integrator configured to integrate a first integrator input signal during a second half cycle of a clock signal and integrate a second integrator input signal during a first half cycle of the clock signal by using a single operational amplifier; a quantizer configured to quantize integrated signals from the at least one integrator and output a first digital signal and a second digital signal; and a feedback loop configured to feed back the first and second digital signals to an input of the at least one integrator. A first analog signal and a second analog signal respectively input from two input paths are respectively converted to the first and second digital signals using the single operational amplifier, thereby increasing power efficiency and reducing an area.

Claims10

Dependent claims

A two-path sigma-delta analog-to-digital converter comprising:

at least one integrator configured to integrate a first integrator input signal during a second half cycle of a clock signal and integrate a second integrator input signal during a first half cycle of the clock signal by using a single operational amplifier, the first and second integrator input signals respectively corresponding to a first analog signal and a second analog signal respectively input from two input paths;
a quantizer configured to quantize integrated signals from the at least one integrator and output a first digital signal and a second digital signal;
and
a feedback loop configured to feed back the first and second digital signals to an input of the at least one integrator.

1 more element

An image sensor comprising:

a pixel array including a plurality of pixels each of which is connected to a corresponding column line among a plurality of column lines and a corresponding row line among a plurality of row lines, each of the plurality of pixels being configured to convert an optical signal into an electrical pixel signal;
and
a two-path sigma-delta analog-to-digital converter (ADC) connected to two corresponding column lines among the plurality of column lines, the ADC being configured to alternately convert a first analog input signal into a first digital signal during a first half cycle of a clock signal and convert a second analog input signal into a second digital signal during a second half cycle of the clock signal, the first analog signal being based on pixel signals of a first corresponding column line, the second analog signal being based on pixel signals of a second corresponding column line.

Dependencies are inferred from the claim text.

Two-path sigma-delta analog-to-digital converter and image sensor including the same

Life of this patent

Two-path sigma-delta analog-to-digital converter and image sensor including the same

Life of this patent

Abstract

Claims10