Analog-digital converting device and method, and image sensor including the same

Patent metadata

Field	Value
Publication number	US-10057517-B2
Application number	US-201715435500-A
Country	US
Kind code	B2
Filing date	Feb 17, 2017
Priority date	Jun 3, 2016
Publication date	Aug 21, 2018
Grant date	Aug 21, 2018

Abstract

An analog-digital converting device includes a comparison block generating at least one first comparison signal by comparing pixel signals with each other, and for generating second comparison signals by comparing each of the plurality of pixel signals with a ramp signal through a single ramping operation; a feedback control unit determining a data conversion sequence according to the at least one first comparison signal received from the comparison block, and outputting a control signal according to the determined data conversion sequence; a selection block selecting two of the plurality of the pixel signals or at least one of the plurality of the pixel signals and the ramp signal to be applied to the comparison block according to the control signal received from the feedback control unit; and a data conversion unit performing a data conversion on the plurality of pixel signals based on the second comparison signal.

First claim

What is claimed is:

1. An analog-digital converting device, comprising:
a comparison block suitable for generating at least one first comparison signal by comparing a plurality of pixel signals with each other, and for generating a plurality of second comparison signals by comparing each of the plurality of pixel signals with a ramp signal through a single ramping operation;
a feedback control unit suitable for determining a data conversion sequence according to the at least one first comparison signal received from the comparison block, and outputting a control signal according to the determined data conversion sequence;
a selection block suitable for selecting two of the plurality of the pixel signals or at least one of the plurality of the pixel signals and the ramp signal to be applied to the comparison block according to the control signal received from the feedback control unit; and
a data conversion unit suitable for performing a data conversion on the plurality of pixel signals based on the second comparison signal.

2. The analog-digital converting device of claim 1 ,
wherein the comparison block includes a comparator suitable for comparing the selected pixel signals among the plurality of pixel signals with each other, and for comparing a selected pixel signal among the plurality of pixel signals with the ramp signal, and
wherein the comparison block further removes an offset by resetting the comparator through a reference pixel signal.

3. The analog-digital converting device of claim 1 , wherein the comparison block compares each of the plurality of pixel signals, which are selected according to the control signal, with the ramp signal according to the determined data conversion sequence.

4. An analog-digital converting method, comprising:
performing a reset operation;
generating a first comparison signal by comparing a plurality of pixel signals with each other;
determining a data conversion sequence according to the first comparison signal;
generating a control signal according to the determined data conversion sequence;
selecting the plurality of pixel signals and a ramp signal according to the control signal; and
performing a data conversion on the plurality of pixel signals by comparing each of the plurality of pixel signals, which are selected according to the control signal, with the ramp signal through a single ramping operation.

5. The analog-digital converting method of claim 4 , wherein the performing of the reset operation includes removing an offset for the comparing of the plurality of pixel signals with each other using a reference pixel signal.

6. A complementary metal oxide semiconductor (CMOS) image sensor, comprising:
a pixel array suitable for outputting a pixel signal corresponding to an incident light;
a row decoder suitable for selecting and controlling a pixel at each row lines of the pixel array;
a ramp signal generation unit suitable for generating a ramp signal;
a comparison unit suitable for comparing a plurality of pixel signals outputted from the pixel array, determining a data conversion sequence of the pixel signals, and comparing each of the plurality of pixel signals with the ramp signal through a single ramping operation;
a counting unit suitable for counting a clock according to a comparison signal of the comparison unit;
a memory unit suitable for storing a counting information of the counting unit; and
a column read-out circuit suitable for outputting a data of the memory unit.

7. The CMOS image sensor of claim 6 , wherein the comparison unit includes
a comparison block suitable for generating a first comparison signal by comparing the plurality of pixel signals with each other, and generating a second comparison signal by comparing each of the plurality of pixel signals with the ramp signal through the single ramping operation;
a feedback control unit suitable for determining the data conversion sequence according to the first comparison signal, and outputting a control signal according to the determined data conversion sequence;
a selection block suitable for selecting the plurality of pixel signals and the ramp signal applied to the comparison block according to the control signal; and
a data conversion unit suitable for performing a data conversion on the plurality of pixel signals based on the second comparison signal.

8. The CMOS image sensor of claim 7 , wherein the comparison block includes a comparator suitable for comparing the selected pixel signals among the plurality of pixel signals with each other, and for comparing a selected pixel signal among the plurality of pixel signals with the ramp signal, and
wherein the comparison block further removes an offset by resetting the comparator through a reference pixel signal.

9. The CMOS image sensor of claim 8 , wherein the comparison block compares each of the plurality of pixel signals, which are selected according to the control signal, with the ramp signal according to the determined data conversion sequence.

Assignees

• Sk Hynix Inc

Inventors

• Kim Tae-Gyu

Classifications

• H04N25/65

  applied to reset noise, e.g. KTC noise related to CMOS structures by techniques other than CDS · CPC title

• H04N25/616 Primary

  involving a correlated sampling function, e.g. correlated double sampling [CDS] or triple sampling · CPC title

• H04N5/378

  Electricity · mapped topic

• H03M1/123

  Simultaneous, i.e. using one converter per channel but with common control or reference circuits for multiple converters · CPC title

• H04N5/37455

  Electricity · mapped topic