FAQ: How to find the perfect SOM form-factor for your application

Date : 19. October 2022

The most frequently asked questions from the webinar on "The perfect SOM form-factor for your next SOM project" on 18.10.2022 are answered here by Product Manager Andreas:

1. Is there an additional fee for using industry standards (e.g. license for SGET)?
   No. At least for SOMs based on the SGET standard we do not charge a fee.
    
2. Does DH electronics support CIP (Civil Infrastructure Platform) Linux?
   Yes. Our current officially supported Linux kernel version is the 5.10 kernel. The CIP project decided this year to extend the super-long-term stable (SLTS) kernel family to include the 5.10 kernel. Therefore we can also support the CPI Linux platform.
    
3. Does DH electronics have any known problems with connectors in terms of robustness and reliability?
   No. We have no problems with the SODIMM-200 socket we use, as it is very resistant to mechanical shock and vibration. The prerequisite for this is that the module can be screwed into the corresponding application. This must be ensured for each SOM.
    
4. Why is a cooling concept needed for SOMs with the STM32MP1, which is only a dual cortex A7?
   As shown in our example, the STM32MP1 gets 90 °C hot without cooling. Since the specified temperature range is up to 125 °C, cooling is basically not required. However, if you now have a simple cooling solution like our 5-Cent Cooling Solution and can reduce the CPU heat by 20 °C to 25 °C with it, the lifetime of the chip is significantly reduced. This means the system can be used in the field for longer - exactly what we want in the industry.
    
5. Why does DH electronics rely on Mainline Linux and not the vendor-based solutions from NXP or ST? I think these vendor-based solutions provide much better support and device drivers for the SoC.
   In some cases, it is certainly true that the vendor-based downstream BSP offers optimized drivers for a particular SoC. BUT: The problem is usually that the manufacturers do not offer maintenance over a longer period of time (e.g. more than two years). As a user, you then have to update to a new version and virtually start from scratch. In contrast, maintenance for mainline Linux is longer and it is easier to upgrade to new versions, especially if you have support for your product upstream. In addition, all drivers are optimized over time. When a new SoC is released, the driver situation is often not ideal. However, after 2-3 years it gets better and better and in most examples you can see a break-even where the mainline support is better than the downstream version. The reason for this is that manufacturers focus more on new products, but the community continues to work on these "old" products. 
    
6. What do you think about the new Open Standard Module?
   In fact, OSM is a new standard for solderable and scalable embedded computer modules. So we will see in the next few years how the standard will be accepted by the market. At DH electronics, we have of course also taken a very close look at the new standard and have come to the decision not to use it for the time being. There are two main reasons for this: a) Some interfaces that we often need in projects are not available. For example, size 0 has no RGB display interface and only the large size L supports LVDS. Both are often needed in our projects. b) We now have very small solderable SOMs that require many nets to be routed from the top to the bottom of the board. At DH we feel that this works best with a custom design without a standard such as our DHCOR modules.
    
7. Why does DH electronics not use industry standards?
   We use SoCs that are more or less low-end solutions in terms of performance (i.MX6ULL, STM32MP1, ...). As mentioned before, industry standards cause higher additional costs due to the partial lack of compatibility. This is the main reason why we have our own solutions today. For low-end solutions, price is very important and this is only possible with individual solutions or manufacturer standards. 
    
8. What system-on-modules are planned for the next three years?
   Today we have a gap between the STM32MP1 and our i.MX8M Plus. So I'm pretty sure we will close this gap with a mid-range design. The SoC is not yet decided and the form factor is also still open.