INDUSTRIAL BY DESIGN
Consumer Grade products are often mistakenly used in place of Industrial. They initially appear to meet the needs of a specific application and it easy to see why.
On the surface they look the same. Identical mechanical design, same capacity and matching form factors.
However there are significant differences between Industrial and Consumer grade flash devices. It is important to consider the impacts these differences have on reliability, endurance, compliance and total cost of ownership before selecting a device that is right for you.
Industrial Grade products are tested for extended periods in operation at wide temperature ratings of -45°C to +85°C. Some manufacturers also have the ability to increase the rating through screening or conformal coating options. Consumer Grade products are rated at only 0°C to +70°C.
Controlled BOM (Build of Materials)
Industrial Grade products have a controlled BOM which specifies there will be no changes to firmware, NAND, controller or customisation undertaken without the notice of a product change notification (PCN). Consumer products do not adhere to the same control and several changes are made during the products short lifetime.
Due to the rapidly changing nature of MLC NAND components and the sheer volume of units being sold when a product using Consumer Grade becomes end of life usually it is there one day and gone the next. Industrial products come with a 3 or 6 months product change notification and last time buy option for all items bought or sampled.
Flash Device Intelligence
The type of NAND memory selected on its own is not enough to determine data integrity and reliability levels. Whilst NAND defines the maximum endurance capabilities, the a device, in order to function must rely on the ‘brains’ which is determined by the controller and firmware design. The advantage of industrial controllers and firmware versus consumer is they have been designed specifically to address the high endurance demands of industrial computing applications. Developed from the ground up the emphasis is placed on core characteristics of reliability and data integrity. In comparison consumer grade controllers need to appeal to a mass market, this means typically they are a ‘one size fits all’ solution that has been developed with a primary focus on cost and meeting the minimum specifications required to be acceptable.
In order to increase reliability there are a whole host of intelligent firmware techniques available in the market for both industrial and consumer flash storage devices. The most commonly known are Wear Levelling, Error Checking & Correction (ECC) and Defect Management. Similar to NAND there are different levels of each and Industrial device manufacturers ensure they are using the highest available level and invest heavily into the R&D of bespoke firmware to further improve them. The objective is to provide firmware that improves reliability and offers long term availability without the need to change. Consumer grade manufactures do not place such an importance on long term availability as the products have much shorter life cycles. Because of the competitiveness of this market there are immense pressures on cost, performance and time to market. For these reasons often the lower level options are selected as they are fit for purpose within consumer grade applications.
Cost & Capacity
One of the main drivers for using Consumer Grade technology into industrial applications is cost. The price per gigabyte (GB) is considerably less when compared at base cost against Industrial. However this does not tell the whole story. In the event of the flash disk becoming corrupt before the life of the application is complete, often the total cost of ownership (TCO) is higher. Just taking into consideration down time, engineering resource (testing and support), reputation, damage, loss of data and the cost of replacing the wrong devices, you begin to understand why. Maximum capacities of industrial are always lower as they do not take advantage of the 2bit and 3bit MLC/TLC structures due to the trade of with endurance and reliability. Because of how long industrial applications must remain operational for and be supported in the field, the minimum capacities are still available from Industrial Grade Manufacturers. Consumer Grade manufacturers move upwards much quicker as they require the ‘sweet spot’ where a capacity provides the best yield based on $/GB.
Consumer Grade products have typical purchase availability of 6-12 months before being replaced or superseded. Industrial Grade products using SLC will exist for >10 years with one or two Product Change Notifications during that time. Industrial Grade MLC products are available for 2-3 years with two or three Product Change Notifications during that time.