In recent years, storage technology has advanced by leaps and bounds, providing increasingly efficient and reliable solutions. One of the developments in this field is ePMR (Enhanced Perpendicular Magnetic Recording) technology applied to hard drives (HDDs) and developed by Western Digital (WD). In this article, we will explore what ePMR technology is, its advantages, applications, and the impact it may have on the future of data storage.
What is ePMR?
ePMR technology is an evolution of Perpendicular Magnetic Recording (PMR), which revolutionized the way data is recorded on hard drives. While traditional PMR allows for higher storage density compared to longitudinal recording, ePMR takes this to a new level. This technology uses a vertical recording structure that allows more bits of information to be stored in a smaller area, resulting in hard drives with greater capacity.
How Does ePMR Technology Work?
The basic principle of ePMR involves passing an additional electrical current through the recording head structure very close to the media surface, which significantly reduces the recorder's inherent timing jitter. This jitter is a noise effect in the recording process that makes recordings slightly inconsistent.
WD has discovered that introducing an additional active current through the magnetic recording device during the recording operation creates an additional magnetic field that reduces the jitter in the recording currents and allows for more precise control over the recording process.
Jitter with and without ePMR - Image Credit: Disclosure
The recording head then comprises a first recording assist element coupled in series with a second recording assist element. The first recording assist element is a Field Effect ePMR (FEePMR) element with an inductance, and the second recording assist element is an ePMR element with a resistance.
The FEePMR element is called a field effect ePMR because it is an assist element that provides an assist effect to the primary recording field generated by the recording pole or main pole driven by the recording coil.
A first recording assist current is synchronized with the recording data current that is driven in the first recording assist element, and a second DC recording assist current is driven in the second recording assist element.
This approach allows for more precise control over the recording process, but it brings additional challenges, particularly related to heat.
The passage of electrical current generates heat, especially in very small areas, such as the magnetic gap of the recording head, which is only tens of nanometers wide. This heat can be a problem because if the temperature gets too high, it can compromise the reliability of the device.
It is crucial to find a balance: too much current can lead to overheating, while too little current may not fully exploit the potential of ePMR technology. Therefore, engineers need to determine the optimal amount of current that maximizes performance without causing thermal damage, because in addition to the heat generated in the recorder, the temperature of the disk itself can become problematic.
Recording head. Red = relative field from ePMR current - Image Credit: Disclosure
Advantages of ePMR Technology
1. Increased Storage Capacity
One of the biggest advantages of ePMR is the ability to offer hard drives with significantly more storage. This is especially important in a world where the amount of data generated and stored is growing every day. From high-definition photos and videos to large corporate databases, the demand for storage is relentless. With ePMR, manufacturers can offer HDDs with higher capacity without increasing the physical size of the device.
2. Improved Performance
In addition to increasing capacity, ePMR technology also improves the overall performance of hard drives. Bit stability and the efficiency of the recording process result in faster read and write speeds, which are crucial in IT environments that require rapid access to large volumes of data.
3. Reduced Energy Consumption
Energy efficiency is a vital factor in the operation of any electronic device. By optimizing the write and read process, ePMR can reduce the power consumption of hard drives, resulting in lower operating costs and a reduced environmental impact. This feature is especially attractive for data centers looking to minimize their carbon footprint.
4. Improved Reliability
ePMR provides improved reliability compared to older recording technologies because it incorporates more advanced error correction algorithms, contributing to the overall reliability of the device.
Applications of ePMR Technology
ePMR technology has a wide range of applications in various areas.
Enterprise Storage
Enterprises that handle large volumes of data, such as cloud service providers, banks, and telecommunications companies, can greatly benefit from the capacity of ePMR HDDs. The secure and efficient storage of sensitive data is crucial for these organizations, making ePMR an attractive choice.
The entertainment industry, especially in terms of the production and storage of high-definition video, also benefits from ePMR. With the increasing demand for 4K and 8K content, storage capacity becomes a central concern. Hard drives with ePMR technology can effectively meet this need.
Conclusion
ePMR technology represents a significant advancement in magnetic recording, but it brings with it complex technical challenges, especially regarding temperature management. The interplay between electrical current, heat generation, and data stability is a critical factor in the success of this technology, requiring a careful balance to maximize both performance and reliability.
