Flash memory products are an essential part of almost all electronics around us and are seen as a commodity; however, this is far from the reality in industrial equipment applications. Without a clear understanding of the scenario, it’s easy to make the mistake of assuming that all flash products are the same and make choices based purely on price per gigabyte. Many design engineers are unclear about the difference between high-quality flash products and low-quality flash products, and just because a new high-capacity flash product is on the market doesn’t mean it’s reliable. At the system level, the choice of a flash controller is more important than the choice of the flash product itself, because the controller and the flash device together determine the quality level of the flash product; therefore, both aspects need to be considered as a whole. This article will present some research on the trade-offs, highlighting why flash systems such as SSD drives, USB drives and the like are not “created equal” and why there are some key factors that engineers must consider when purchasing flash products for their industrial equipment designs.
For consumer electronics, although the working environment temperature will vary slightly, most of the time we will use the computer at an ambient temperature of 20 ℃. Generally speaking, the operating temperature range for consumer electronics is 0 to 40°C, with some applications reaching 60°C. However, in industrial applications, the operating temperature or operating temperature range can be more extreme. However, in industrial applications, the operating temperature or operating temperature range can be more extreme. The conventional definition of the industrial-grade temperature range is -40 to 85°C, and there are a number of potential risks when using non-industrial flash memory devices and controllers in industrial scenarios. Industrial engineers are not comfortable with the concept of failure because production downtime and production restarts are very expensive accidents. Sudden, uncontrolled device failures can also be costly, costly to fix, and can further cause outages.
You may ask why I can’t spend $10 for a 32GB USB flash drive at a retail store and $30 for another one that looks identical. We’ll answer this question in more detail, but you may have noticed that every module in an industrial application is rigorously tested with pre-defined use cases to ensure a consistently high level of quality for a long enough lifecycle.
Reliability of industrial specifications begins with design and manufacturing
Hyperstone’s flash controller products for industrial applications are based on proprietary IP designs that are far more stringent in terms of reliability and fail-safe than those for consumer products. When the design process is focused on temperature characteristics, hardware timing is critical, requiring significant time and potentially increased die area to ensure reliability at each temperature node. The features have evolved over the years and always come with built-in reliability guarantees, and each new controller release will continue to include support for different industry case features.
Firmware development is another key factor, which also requires industrial thinking in the design process and close integration with the hardware design.
Finally, testing is a very important aspect, which corresponds to the conduction system for industrial applications. In addition to temperature cycling, sudden power failure testing is also an important part of the process. Hyperstone is able to validate new products and their firmware through a rigorous set of power cycling tests that simulate a full set of outage scenarios that must ensure that data is not lost when power is restored to the system in order to maintain data integrity.
Another important factor to consider when using flash memory products is data retention time, which is highly dependent on operating temperature. Data in flash memory is lost over time, and the higher the ambient temperature, the greater the percentage of data loss. Data loss occurs regardless of whether the device is active or not, which is another reason to focus on the temperature factor. The data retention time for flash products is generally described as 25°C, but in industrial applications, it is common for devices to operate at 60°C, a factor that has a profound effect on data retention time. For example, if the temperature of the storage system is raised from room temperature to 60°C, the data retention ratio will be reduced by 20%; this sounds like a lot to lose, but it is because data will be lost within 6 months instead of 10 years at 60°C. The data retention ratio will be reduced by 20%. Data protection can be achieved by choosing the right flash device in conjunction with the controller’s flash refresh management mechanism.
Product support: ensure product design meets industrial-grade requirements
Few vendors have true long-term support and service, and flash memory and controller vendors need to be involved from initial product concept to product maturity. Hyperstone is committed to the long term, just as it is still providing support and service for its CF card controller products, which were launched in 2003.
Hyperstone engages with its customers as early as possible to establish interaction and then ensure that their designs meet their application needs, our first question might be “What is your application scenario?”. We use a case indexing tool to work with our customers to evaluate how an application accesses and stresses the storage product. We are able to optimize the firmware by adjusting specific parameters such as access method, read/write speed, access frequency, etc., to select the correct configuration and capacity to maximize reliability and provide the best cost.
Hyperstone has integrated debugging interfaces and protocol features into the controller and its firmware architecture so that if an error occurs we can analyze what went wrong. 99.9% of the time we know what happened and can take action quickly to prevent similar errors from happening again. And consumer flash memory controllers can’t do that at all.