Mirrored Stacked Dual Reader for High-Density Magnetic Storage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In magnetic data storage systems, the increasing recording density on magnetic discs requires smaller MR sensors and narrower shield-to-shield spacing to improve signal-to-noise ratio, but existing stacked dual readers face challenges with noise and instability due to opposite polarities of leads connected to mid-shields, leading to increased insulator thickness and reduced performance under skew.
Innovation Solution
The implementation of a stacked dual reader design where the bottom and top sensor stacks are mirrored along the down-track direction, with the same polarity leads connected to mid-shields, reducing the shield-to-shield spacing and the distance between sensor stacks, thereby improving stability and reducing noise while maintaining performance under skew.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If opposite polarity leads are connected to mid-shields in existing stacked dual readers, then the structure can be implemented, but noise and instability increase
Solution Approach 1:
The patent inverts the conventional lead connection approach by connecting leads with the same polarity to both mid-shields instead of opposite polarities. This reversal of the traditional design eliminates the noise and instability issues that arose from opposite polarity connections, while maintaining manufacturing feasibility.
2Reliability
If insulator thickness is increased to compensate for noise, then insulation performance improves, but device complexity and size increase
Solution Approach 1:
The patent extracts and eliminates the need for thick insulators by removing the source of the problem - the opposite polarity lead connections. By adopting same polarity connections, the design removes the requirement for excessive insulation, thereby reducing device complexity and size while maintaining adequate insulation performance.
3Measurement precision
If shield-to-shield spacing is narrowed to improve signal-to-noise ratio, then recording density increases, but manufacturing precision requirements increase
Solution Approach 1:
The patent applies beforehand cushioning by using same polarity lead connections that inherently reduce noise and instability. This creates a buffer against the challenges of narrow shield-to-shield spacing, allowing the system to achieve high signal-to-noise ratios without imposing excessively tight manufacturing precision requirements on the shield spacing.
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
This design enhances the signal-to-noise ratio and reduces noise and instability, allowing for better performance in high-density recording and improved stability by minimizing the distance between sensor stacks and reducing the thickness of the insulator, thus maintaining performance under skew conditions.
Implementation Method 1
a magnetoresistive (MR) sensor for retrieving magnetically encoded information stored on a magnetic disc. Magnetic flux from the surface of the disc causes rotation of the magnetization vector of a sensing layer of the MR sensor, which in turn causes a change in electrical resistivity of the MR sensor
Data Source
AI summary
Implementations described and claimed herein provide a stacked dual reader with a bottom sensor stack and a top sensor stack wherein the bottom sensor stack and the top sensor stack are mirrored along a down-track direction.