As was outlined in an earlier article on this blog, it is critical for manufacturers to characterize solid-state drives (SSD) to establish performance parameters in real-world conditions. The previous article explained that SSD experience higher failure rates and reduced lifespan when temperatures increase beyond the standard operating range of 30-40°C.
Testing processes for SSD are similar to those used for characterizing typical semiconductors. A wind tunnel provides a consistent, controlled, and repeatable environment for data collection and sensors, thermocouples, and an analog-to-digital capture system allows engineers to measure performance when the SSD is impacted by external factors.
ATS designs and fabricates research-quality wind tunnels that can be used for characterizing SSD. The wind tunnels give engineers control over air temperature and velocity. Closed-loop wind tunnels can create environments with temperatures as high as 80°C to provide stressed conditions well above standard operating temperatures. The manufacturer can use this data to set reference points for different environments, such as in 1-U telecommunications chassis or large server boxes.
Recently, ATS has worked with two of the industry’s largest producers of SSD to design wind tunnels that could be used for characterizing drives in PCIe applications. PCIe (peripheral component interconnect express) cards are high-speed serial computer extension cards that connect peripheral devices to the motherboard. In addition to SSD, these cards can be used for graphics processors, Wi-Fi, or other hard drives.
One of the wind tunnels was a standard, open loop CWT-107™. It can produce uniform and homogeneous flow, up to 5.5 m/s (1100 ft/min) within the wind tunnel’s test section due to its polynomial shape and internal flow management system, which features honeycombs and screens to break up turbulence. The wind tunnel can be operated either vertically or horizontally and the customer chose to use it lying down.
In fact, the customer was very creative in its use of the wind tunnel. A customized cart was built for the wind tunnel to be bolted to and then the cart was wheeled into a large environmental chamber where temperatures could be raised to test levels. The SSD being characterized was a PCIe card with memory installed. There was no fan for the memory and the memory had no shielding or housing.
The customer placed its PCIe-based SSD flat in the test chamber. Power was pulled through the test ports included in the test chamber of the CLWT-107™ (as shown below).
While the wind tunnel was bought for testing SSD, it could be used by the customer to test any electronic component or board.
The second customer purchased a CLWT-115™ closed-loop wind tunnel. In this case, the application required the SSD to be powered through the PCIe back plane, so ATS custom-designed slots in the test section to fit the PCIe form factor. The slots allowed the SSD to remain inside the test section and be connected to a motherboard residing outside the wind tunnel (see below).
Again, the wind tunnel could be used to test any PCIe cards, not just SSD, if the customer desired, as there were also fillers created for the slots to allow the wind tunnel to be used when testing other devices.
The second customer did all of its air velocity and temperature testing in the CLWT-115™, rather than using an environmental chamber like the first customer, because the wind tunnel has a self-contained heating unit that heats air while it circulates during testing.
Wind tunnel controllers and ATVS systems were also purchased by both customers to ensure accurate data collection. The first customer bought an ATVS-NxT™, which is a fully portable scanner that operates with an embedded PC and touch screen control, while the second customer bought the ATVS-2020™, which allows single- or multi-point measurement of both temperature and velocity, and a CLWTC-1000™, which automatically controlled the airflow and temperature through the test chamber.
Both come with Candlestick sensors to control the air velocity in the wind tunnel and thermocouples to control the temperature.
One of the customers also requested a custom, rugged sensor to avoid damage through multiple uses. ATS was able to adapt one of its handheld surface probes, a stainless-steel probe with a pointed tip for exact positioning of the sensor on the desired spot, by reducing the length and designing a custom port that would hold the sensor in place.
SSD are gaining traction in the market, with major hard drive manufacturers and the companies that utilize them both making the switch to solid-state technology. This means that thermal characterization of SSD and thermal management systems deployed to dissipate the heat of these drives are going to be of increasing importance in the coming years.
Using research-quality wind tunnels gives manufacturers a leg up in determining how their drives will perform in different real-world environments and makes the process of SSD characterization easier for users. By working with ATS, companies can tailor their wind tunnels to their specific applications and can be assured of the accuracy of the data that they collect.
Learn more about ATS wind tunnels, sensors, and the entire line of next-generation thermal test instruments at https://www.qats.com/Products/
Instruments. If you have questions about any products or ATS thermal testing services, email ats-hq@qats.com.
For more information about Advanced Thermal Solutions, Inc. (ATS) thermal management consulting and design services, visit https://www.qats.com/consulting or contact ATS at 781.769.2800 or ats-hq@qats.com.
