Delta-Sigma Integrator Readout for Small-Signal Bit-Line Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional sense amplifiers struggle to accurately distinguish small differences in voltage or current levels in multi-bit memory elements and light sensors due to noise interference, leading to reduced memory density and imaging device performance.
Innovation Solution
A quantizing circuit that samples electrical parameters multiple times and filters the samples to reduce noise, allowing for the detection of small differences and enabling the use of multi-bit memory elements and increased sensitivity in imaging devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional sense amplifiers are used to read multi-bit memory elements, then the memory device can be manufactured with standard circuits, but the sense amplifiers cannot accurately distinguish small differences in voltage or current levels due to noise interference
Solution Approach 1:
The patent applies periodic action by using a delta-sigma modulator that samples the memory element signal multiple times at different periods. The modulator performs repeated measurements and uses digital filtering to average out noise, thereby improving the ability to distinguish small signal differences while maintaining immunity to noise interference.
2Reliability
If the number of readable states of the memory element is reduced to improve noise immunity, then the sense amplifier can operate more reliably, but the memory density decreases
Solution Approach 1:
The patent changes the parameter of signal processing by transitioning from direct single-shot analog comparison to multi-sample digital processing. The delta-sigma modulator converts the analog signal to a digital bitstream through repeated sampling, allowing full utilization of multi-bit memory element states while achieving noise immunity through digital filtering rather than limiting the number of readable states.
3Quantity of substance
If multi-bit memory elements are used to increase memory density, then more data can be stored per element, but the voltage difference between levels becomes smaller and harder to distinguish
Solution Approach 1:
The patent introduces a delta-sigma modulator as an intermediary between the memory element and the readout circuitry. This modulator acts as a signal conditioner that amplifies small voltage differences through noise shaping and oversampling, converting difficult-to-measure small analog differences into easily distinguishable digital bitstreams with enhanced precision.
4Device complexity
If conventional sense amplifiers are used in imaging devices, then the device structure remains simple, but noise reduces the fidelity of captured images
Solution Approach 1:
The patent replaces the conventional analog sense amplifier mechanism with a digital-based delta-sigma modulation system. This substitution transitions from direct analog voltage comparison prone to noise to a digital sampling and filtering approach, significantly improving image fidelity while maintaining acceptable structural complexity through integration of the modulator with existing pixel circuits.
Data Source
AI summary
Methods, systems and devices are disclosed. Among the disclosed devices is an electronic device that, in certain embodiments, includes a plurality of memory elements or imaging elements connected to a bit-line and a delta-sigma modulator connected to the bit-line. The delta-sigma modulator may include an integrator having a differential amplifier.