Image sensor chip that feeds back voltage and temperature information, and an image processing system having the same

Patent metadata

Field	Value
Publication number	US-10827144-B2
Application number	US-201916658522-A
Country	US
Kind code	B2
Filing date	Oct 21, 2019
Priority date	May 23, 2016
Publication date	Nov 3, 2020
Grant date	Nov 3, 2020

Abstract

An image sensor chip includes an internal voltage generator for generating internal voltages using an external voltage received at a first terminal of the image sensor chip, a temperature sensor for generating a temperature voltage, a selection circuit for outputting one of the external voltage, the internal voltages, and the temperature voltage, a digital code generation circuit for generating a digital code using an output voltage of the selection circuit, and a second terminal for outputting the digital code from the image sensor chip.

First claim

What is claimed is:

1. An image sensor chip, comprising:
an internal voltage generator configured to generate internal voltages using an external voltage received at a first terminal of the image sensor chip;
a selection circuit configured to output one of the internal voltages and a temperature voltage;
a digital code generation circuit for generating a digital code using an output voltage of the selection circuit; and
a second terminal configured to output the digital code from the image sensor chip, and
wherein the image sensor chip is configured to receive the temperature voltage from a temperature sensor.

2. The image sensor chip of claim 1 , wherein the digital code corresponds to the internal voltages or the temperature voltage.

3. The image sensor chip of claim 1 , wherein the digital code generation circuit includes:
an attenuator for generating a second output signal by attenuating a first output signal of the selection circuit; and
a first analog-to-digital converter for converting the second output signal into the digital code.

4. The image sensor chip of claim 1 , further comprising an encoder for encoding the digital code and generating a control signal according to a result of the encoding, wherein the internal voltage generator adjusts one of the internal voltages in response to the control signal.

5. The image sensor chip of claim 1 , wherein the digital code generation circuit includes a first analog-to-digital converter for generating the digital code using an output signal output from the selection circuit,
the image sensor chip includes:
a pixel; and
a second analog-to-digital converter for converting a pixel signal output from the pixel into a digital signal, and
a structure of the first analog-to-digital converter is the same as a structure of the second analog-to-digital converter.

6. The image sensor chip of claim 1 , wherein the digital code generation circuit includes:
a comparator including a first input terminal and a second input terminal;
a first switch and a second switch connected to an output terminal of the selection circuit;
a first capacitor connected between the first switch and the first input terminal;
a second capacitor connected between the second switch and the first input terminal;
a third switch connected between a common node of the first switch and the first capacitor and a ground;
a third capacitor connected between a terminal for receiving a ramp signal and the second input terminal; and
a counter connected to an output terminal of the comparator.

7. The image sensor chip of claim 1 , wherein the internal voltage generator generates a first internal voltage higher than the external voltage and a second internal voltage lower than a ground voltage as the internal voltages.

8. The image sensor chip of claim 1 , wherein the internal voltage generator generates a first internal voltage higher than the external voltage and a first intermediate voltage related to the first internal voltage as the internal voltages,
the selection circuit outputs the first intermediate voltage, and
the digital code generation circuit generates the digital code using the first intermediate voltage.

9. The image sensor chip of claim 1 , wherein the internal voltage generator generates a first internal voltage higher than the external voltage, a first intermediate voltage related to the first internal voltage, and a second intermediate voltage related to the first intermediate voltage as the internal voltages,
the selection circuit sequentially outputs the second intermediate voltage and the first intermediate voltage, and
the digital code generation circuit generates the digital code using the second intermediate voltage and the first intermediate voltage.

10. The image sensor chip of claim 1 , wherein the internal voltage generator generates a first internal voltage lower than a ground voltage and a first intermediate voltage related to the first internal voltage as the internal voltages,
the selection circuit outputs the first intermediate voltage, and
the digital code generation circuit generates the digital code using the first intermediate voltage.

11. The image sensor chip of claim 1 , wherein the temperature sensor is disposed inside of the image sensor chip.

12. The image sensor chip of claim 1 , wherein the temperature sensor is disposed outside of the image sensor chip.

13. An image processing system, comprising:
an external voltage supply device;
an image sensor chip configured to receive an external voltage supplied by the external voltage supply device; and
an application processor connected to the image sensor chip and the external voltage supply device,
wherein the image sensor chip includes:
an internal voltage generator configured to generate internal voltages using the external voltage;
a selection circuit for outputting one of the internal voltages and the temperature voltage;
a digital code generation circuit configured to generate a digital code using an output voltage of the selection circuit; and
an output terminal for transmitting the digital code to the application processor, and
wherein the image sensor chip is configured to receive the temperature voltage from a temperature sensor.

14. The image processing system of claim 13 , wherein the application processor generates a voltage control signal using the digital code, and
the internal voltage generator adjusts the internal voltages in response to the voltage control signal.

15. The image processing system of claim 14 , wherein the digital code generation circuit includes:
an attenuator for generating a second output signal by attenuating a first output signal of the selection circuit, and
an analog-to-digital converter for converting the second output signal into the digital code.

16. The image processing system of claim 14 , wherein the digital code generation circuit includes a first analog-to-digital converter for generating the digital code using an output signal output from the selection circuit,
the image sensor chip further includes:
a pixel, and
a second analog-to-digital converter for converting a pixel signal output from the pixel into a digital signal, and
a structure ofthe first analog-to-digital converter is the same as a structure of the second analog-to-digital converter.

17. The image processing system of claim 13 , wherein the temperature sensor is disposed outside of the image sensor chip.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Cho Sang Hyun
• Park Ji Yong
• Paik Dae Hwa
• Koh Kyoung Min
• Kwon Min Ho
• Lim Seung Hyun

Classifications

• H03M1/12 Primary

  Analogue/digital converters ({H03M1/001 – } H03M1/10 take precedence) · CPC title

• H04N25/709 Primary

  Circuitry for control of the power supply · CPC title

• H04N25/76

  Addressed sensors, e.g. MOS or CMOS sensors · CPC title

• H03M1/0845 Primary

  of power supply variations, e.g. ripple · CPC title

• H04N25/78

  Readout circuits for addressed sensors, e.g. output amplifiers or A/D converters · CPC title