HAMR Laser Preamp Interface Circuit for NFT Wear Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Heat-assisted magnetic recording (HAMR) systems face high power consumption and premature failure due to continuous laser light usage, causing excessive wear on near field transducers (NFTs) in data storage devices.
Innovation Solution
A system that determines and manipulates a laser data signal to generate a modulated laser current, which is then used to heat the disc, allowing for efficient HAMR recording while reducing wear on NFTs by using a circuit to control the laser current waveform, including pulse width and current settings, to maintain a predetermined average value.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If continuous laser light is used for HAMR recording, then reliable data storage is achieved, but power consumption increases and NFT wear accelerates
Solution Approach 1:
The patent applies periodic action by replacing continuous laser operation with pulsed laser operation. The laser is activated only during specific time intervals corresponding to data write operations, rather than continuously. This temporal segmentation reduces energy consumption while maintaining recording reliability, as the laser provides sufficient heat during pulse intervals without the waste energy of continuous operation.
Solution Approach 2:
The patent implements dynamics by making the laser current waveform adjustable and adaptive. The circuit manipulates the laser data signal to generate variable pulse widths and current levels based on recording requirements. This dynamic control allows optimization of power consumption during HAMR operations while ensuring adequate heating for reliable data storage.
2Reliability
If continuous laser light is used for HAMR recording, then reliable data storage is achieved, but NFT lifespan decreases due to excessive wear
Solution Approach 1:
The patent applies periodic action by replacing continuous laser operation with pulsed laser operation. The laser is activated only during specific time intervals corresponding to data write operations, rather than continuously. This temporal segmentation reduces energy consumption while maintaining recording reliability, as the laser provides sufficient heat during pulse intervals without the waste energy of continuous operation.
Solution Approach 2:
The patent applies the discarding and recovering principle by stopping laser operation during non-recording periods. The laser current is discarded (turned off) during intervals when data recording is not occurring, and recovered (turned on) only when recording is needed. This cyclic on/off pattern extends NFT lifespan by preventing continuous thermal stress and mechanical wear.
3Use of energy by moving object
If laser current is modulated to reduce power consumption, then NFT wear is minimized, but control complexity increases
Solution Approach 1:
The patent applies the intermediary principle by introducing a dedicated circuit between the laser data signal source and the laser driver. This intermediate circuit manipulates the laser data signal to generate the appropriate current waveform with controlled pulse widths and amplitude. The intermediary circuit handles the complexity of modulation, isolating it from the main laser control path and enabling sophisticated power management without overwhelming system complexity.
Solution Approach 2:
The patent implements parameter changes by adjusting key parameters of the laser current waveform, specifically pulse width and current amplitude. The circuit varies these parameters to optimize power consumption during HAMR operations. By changing temporal and amplitude parameters rather than fundamentally altering the laser operation mode, the system achieves energy efficiency with manageable control complexity.
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
The modulated laser current waveform reduces power consumption and extends the lifespan of data storage devices by minimizing wear on NFTs, ensuring reliable and efficient data storage operations.
Implementation Method 1
a laser configured to heat a data storage medium
Implementation Method 2
determining a laser current required to heat a disc so that write data can be stored
Data Source
AI summary
A circuit may be configured to reduce the power consumption and extend the life of a near field transducer of a heat-assisted magnetic recording (HAMR) device by pulsing a laser. The current that drives the laser may be of a frequency and magnitude so as to approximate the value of a continuous current in a continuous, non-pulsed laser. A system on chip (SOC), which may include a HAMR channel, can generate a laser data signal that may be synchronous with, and offset from, a write signal by a certain period of time, and may calculate certain parameters such as peak current and pulse width that may be applied to the signals in a preamp. The preamp signals can be used to program data to a disc medium.