I want to design an SBC but I am having difficulty with buying the SoC. I'm thinking of Snapdragon, Mediatek, Allwinner, Amlogic and Rockchip (These are the ones I know, if you know others I would appreciate it if you tell me)
I tried Digikey and Mouser and my search was fruitless. How do I procure such chips in low quantities?
You really have to consider the application as there such a broad range and there is an equally broad range of SOCs to apply.
Take for example the STM32F76x series. That could easily be considered to be an SOC with the sheer number of circuit subsystems on it including on board FLASH and RAM.
Or consider another example the Intel C3000 series processor family. The series supports up to 16 64-bit cores and high speed I/O lanes that can be used for SATA, PCIe or USB.
Both of these SOCs have family members that can be purchased in single lot quantities from Mouser.
The big players selling to the consumer market (such as Qualcomm) really aren't interested unless you want to buy in 10k or even 100k / 1M quantities and they rarely (if ever) sell via the type of distribution such as digikey / mouser and so forth.
They are more likely to be with Avnet and it's subsidiaries, Arrow or another of the big distribution partners but they won't engage with small companies either (not worth the time and effort from their perspective). They also sell direct to their premium partners (who are buying massive quantities of parts usually measured in millions).
I have run into that with GPS chipsets a few years ago; we were selling perhaps 100 units per month but this particular supplier was not interested in less than 10k parts per month (not worth their time and effort basically).
What you really need to do is to identify what you want / need your SBC to be capable of and then choose parts that are available based on those criteria.
