Shared Integrator Circuit for Low-Noise Photosensitive Element Groups
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional ambient light sensing devices face challenges with spatial sensitivity due to the large size and high manufacturing costs associated with multiplying photosensitive elements, leading to errors in detecting optical components and increased noise from transmission lines.
Innovation Solution
A photosensitive device with a peripheral circuit semiconductor region and a photosensitive circuit semiconductor region, featuring shared amplification circuits and differential circuits with capacitive feedback, allowing for multiple photosensitive elements without increasing size or cost, and spatially distributing elements for reduced sensitivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the number of photosensitive elements is multiplied to reduce spatial sensitivity, then measurement precision is improved, but device area and manufacturing cost increase
Solution Approach 1:
Multiple photosensitive elements (e.g., four photodiodes) share a common amplification circuit and readout path, allowing spatial distribution of sensing elements without proportionally increasing the number of readout circuits. This merging of readout resources enables improved spatial sensitivity while controlling device area.
Solution Approach 2:
A single amplification circuit serves multiple photosensitive elements, making the readout circuit universal for sensing different optical components (red, green, blue, ultraviolet). This multi-functionality allows the same circuit infrastructure to support multiple sensing functions without proportional area increase.
2Measurement precision
If photosensitive elements are distributed in a large matrix, then spatial sensitivity is reduced, but transmission line noise increases
Solution Approach 1:
Multiple photosensitive elements share common transmission lines and readout circuits, reducing the total number of transmission lines required. This merging approach decreases the cumulative resistive noise from transmission lines while maintaining spatial distribution of sensing elements for reduced spatial sensitivity.
3Object-affected harmful factors
If read circuits are placed in immediate proximity of photosensitive elements, then transmission line noise is reduced, but device complexity and area increase
Solution Approach 1:
Multiple photosensitive elements share a common amplification circuit located in the peripheral circuit semiconductor region, reducing the total number of readout circuits required. This sharing approach decreases device complexity while maintaining acceptable transmission line noise levels through the shared architecture.
4Measurement precision
If the number of photosensitive elements is increased, then spatial sensitivity is reduced, but manufacturing cost increases
Solution Approach 1:
Multiple photosensitive elements share common readout infrastructure including amplification circuits and transmission lines, reducing the per-element cost of adding additional sensing elements. This shared architecture makes it more cost-effective to increase the number of photosensitive elements for improved spatial sensitivity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables precise measurement of ambient light components with reduced spatial sensitivity and noise resistance, allowing for more elements without increasing size or manufacturing costs, while maintaining precision and efficiency.
Implementation Method 1
a feedback circuit for each photosensitive element of the group, comprising a capacitive element located in the photosensitive circuit semiconductor region and connected between the output node of the amplification circuit and the respective critical node
Implementation Method 2
at least one group of at least two photosensitive elements configured to generate a photoelectric signal
Data Source
AI summary
A photosensitive device includes a peripheral circuit semiconductor region, a photosensitive circuit semiconductor region including at least one group of at least two photosensitive elements configured to generate a photoelectric signal on a node called critical node. The device further includes an integrator circuit per group of photosensitive elements, each including: a differential circuit for each photosensitive element of the group, in the photosensitive circuit semiconductor region, an amplification circuit, in the peripheral circuit semiconductor region, and a feedback circuit for each photosensitive element of the group, comprising a capacitive element located in the photosensitive circuit semiconductor region coupled between the output node of the amplification circuit and the respective critical node.