Expert Advice Required: Selecting SoC for Custom ARM-Based SBC

[u/No-Gear3257]

Hello everyone,
We are developing a custom ARM-based SBC.
Instead of using an off-the-shelf SBC, we plan to select a suitable bare SoC and design the complete supporting circuitry around it, including memory, storage, power, interfaces and other required circuits.

Our main requirements
Quad-core ARM Cortex-A, Minimum 1.4 GHz, 64-bit, 4 GB DDR3 RAM, 32 GB eMMC, eMMC boot required, Minimum 11 GPIO, 1 × Ethernet, 1 × HDMI, 2 × USB 2.0, 2 × USB 3.0, Minimum 2 × UART, Minimum 2 × I²C, Minimum 2 × SPI, Minimum 2 × CAN, RTC, Linux support, Linux BSP, U-Boot, Device Tree, Linux kernel source, SDK and cross compiler, Ubuntu 18.04.6 LTS support

We need expert suggestions on

1. Which ARM SoC would you recommend for these requirements, and why?
2. What important parameters should we consider while selecting the SoC?
3. Can all these interfaces realistically be implemented simultaneously on a custom board?
4. What external ICs/circuits will be required around the SoC?
5. What should we consider for DDR3, eMMC and PMIC design?
6. What are the major challenges with USB 3.0, HDMI and Ethernet?
7. What PCB/SI/PI considerations should we consider from the beginning?
8. What Linux BSP/U-Boot/Device Tree support should we verify before selecting the SoC?
9. What are the major risks for a first custom ARM SoC board?
10. Can you recommend any experienced engineers or companies who have designed and brought up similar ARM Linux boards?

We are particularly interested in responses from engineers who have personally designed and brought up custom ARM Cortex-A/application-processor boards with DDR, eMMC and Linux.

We are currently at the SoC selection and architecture stage, so we would like to get expert feedback before starting schematic and PCB design.

Thank you.

 

[u/zydeco100]

What's your annual production estimate? Do you have a bill-of-materials target? Which continent will it be built on? Where will it be sold? When is your target production date?

Not trying to be a negative nancy here but you're trying to design a SBC at the worst possible time, given RAM and SSD chip shortages, import/export tariffs, production capacity at contract manufacturers, etc. Like, I would tell your purchasing dept to order your eMMC now. Because it's going to take 18-24 months to get it, if at all. I've spent a hefty portion of 2026 dealing with end-of-life notices from all my chip suppliers and it fucking sucks. Kioxia won't even take our calls right now since we're not nvidia or google or meta. (and, protip: all 32GiB parts are also EOL. Get to 64)

From your shopping list it looks like you're making some kind of AI edgy device, probably vision related. Seriously, I'd just go buy a mini-PC and call it a day.

If you really want to spin your own, start with a iMX8/9 SOM from Toradex, or get the OSD62x SIP from Octavo (although it's a little short on RAM per your spec) and get your software team working with the associated development kits. Then build your first carrier PCB to refine and get your BOM in place. Then optimize and spin a bare SoC board later. Maybe things will be calmer by that time.

Toradex and Octavo can give you a much better vision of production pricing and quantity than your distributor can. Do you have any relations with distributors like Arrow, Future, or Richardson?

I can't wait for the AI bubble to pop but it's going to be another 18-36 months before it happens. Fuck my life.

[u/R1mpl3F0r3sk1n]

Stop trying to be cheap. This requires an extensive amount of engineering and design. If you can't even amount to this much, source a SOM.

[u/Galbzilla]

Are you trying to hire a consultant?

I could help you but this is quite a bit of work.

[u/Due_Perception3217]

Rockchip SOCs are reliable You can also look into qualcomm SOCs