Pixel Driving Level Shifter for Wide Voltage Swing Imaging

Solution Overview

Problem

Traditional image sensors require a two-stage level shifter that increases circuit complexity and layout area due to the need for multiple transistors to achieve a voltage swing from a positive to a negative voltage potential.

Innovation Solution

The proposed image sensor employs a pixel driving circuit with a specific configuration of transistors, including P-type and N-type MOSFETs, that generates a driving signal with a voltage swing from a positive to a negative voltage potential using fewer transistors, reducing the circuit layout area and preventing light banding in image outputs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a two-stage level shifter is used to generate voltage swing from positive to negative potential, then the driving signal can be generated, but the circuit complexity and layout area increase due to requiring more transistors

Engineering Contradiction:

Improvedriving signal generationVSAvoidcircuit complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges the functions of two separate level shifters into a single integrated circuit. The first level shifter (T1-T4) and second level shifter (T5-T8) are combined with shared power supply connections and coordinated control signals, reducing the total transistor count while maintaining the ability to generate voltage swings from positive to negative potential for driving the pixel circuit

Inventive Principle:

Principle #5Merging (Combining)

2Reliability

If a two-stage level shifter is used to generate voltage swing from positive to negative potential, then the driving signal can be generated, but the layout area increases due to requiring more transistors

Engineering Contradiction:

Improvedriving signal generationVSAvoidcircuit layout area

Core Design Contradiction:

ReliabilityVSArea of stationary object

Solution Approach 1:

The patent merges the functions of two separate level shifters into a single integrated circuit. The first level shifter (T1-T4) and second level shifter (T5-T8) are combined with shared power supply connections and coordinated control signals, reducing the total transistor count while maintaining the ability to generate voltage swings from positive to negative potential for driving the pixel circuit

Inventive Principle:

Principle #5Merging (Combining)

3Reliability

If more transistors are used in the pixel driving circuit, then the voltage swing from positive to negative potential can be achieved, but the power consumption increases

Engineering Contradiction:

Improvevoltage swing capabilityVSAvoidpower consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent merges the functions of two separate level shifters into a single integrated circuit. The first level shifter (T1-T4) and second level shifter (T5-T8) are combined with shared power supply connections and coordinated control signals, reducing the total transistor count while maintaining the ability to generate voltage swings from positive to negative potential for driving the pixel circuit

Inventive Principle:

Principle #5Merging (Combining)

Data Source

PatentUS12192663B2Image sensor, level shifter circuit, and operation method thereof

Publication Date: 2025.01.07 GUANGZHOU TYRAFOS SEMICON TECH CO LTD

AI summary

An image sensor, a level shifter circuit, and an operation method thereof are provided. The image sensor includes a pixel circuit and a pixel driving circuit. The pixel driving circuit includes first, second, third, fourth, fifth, and sixth transistors. A first terminal of the first transistor is coupled to a first voltage. A first terminal of the second transistor is coupled to the first voltage, and a control terminal of the second transistor is coupled to a control terminal of the first transistor and a second terminal of the first transistor. A first terminal of the third transistor is coupled to the second terminal of the first transistor, and a second terminal of the third transistor is coupled to a ground voltage. A first terminal of the fourth transistor is coupled to a second terminal of the second transistor and an output terminal.