Some suggestion on using SOM Modules without support

[Lakshmi]

Hi,

In my project, I'll be using SOM-RK3399(Friendlyarm) with additional functionality like Ethernet, USB etc.

https://www.friendlyarm.com/index.php?route=product/product&product_id=257

Since the schematic file was open source I started with schematic as I asked them for the details of SOM-RK3399 like Gerber/Layout files and BOM. Now they are telling that they can not be shared. Only schematics can be shared.
As this is my first High-speed design I was expecting those Files with design guidelines from them, unfortunately I'll not be able to access them.
One of my senior suggestion is to complete the layout but I'm bit reluctant to that as without Friendly Arm's support.
I'd like to hear your suggestion on this especially @robertferanec

Thank you.

[robertferanec]

What may be useful is to find an open source baseboard for this module (baseboard available with SCH and PCB). For design guidelines, check CPU documentation.

PS: I learned the same lesson .... and now before I start using something in my designs, I carefully check available documentation, development kits and software. Poor documentation is very specific for Chinese chips, so for important designs you may want to use well known manufacturers.

[Lakshmi]

Thank you.
RK3399 baseboard are not open source If you find one could you please link me there?
About the CPU (RK3399) guidelines, they've hardly 5 pages of guidelines they won't cover in depth.

[robertferanec]

I would maybe try to convince my boss, that there is a high risk of ending up with not working or possibly problematic board if we go with that chip (usually that convince him/her as even the boss doesn't want to be responsible for ending up with a non working board). I would try to suggest to search for a new chip with better documentation. PS: Problem is, the cheapest chips have poorest support and documentation .... but because of their low price, some managers are pushing them into their products.

I have never worked with Rockchip so I can not really help with anything else ... just the advice above.

[Paul van Avesaath]

One of my senior suggestion is to complete the layout ..

thats the same as shut up and just do it..



anyway I agree with robert on this heavily, I have designed boards with Qseven, SMARC and Mini PCIe, and good documentation is a must on these but most are very good when you buy from a good vendor or when they have a large userbase.

as robert suggests most of the time your boss will not want to see the issue that is in fornt of him. and if they really want it like this then it is their risk..

good luck

[MrSun]

Hello Lakshmi,here are some docs for reference

1. RK3399 Hardware Design Guide
2. RK3399 TRM

[robertferanec]

Nice design guide. I am surprised. Thank you MrSun for sharing.

[Paul van Avesaath]

you do know that those are confidential documents right .. but still nice find !

[MrSun]

oh,sorry!I just search in google

[robertferanec]

Looks like design guide doesn't say confidential. The other link is pointing to a confidential document and maybe it should be removed. However it is not hard to google it "RK3399 TRM PDF"

[MrSun]

sometimes searching for keywords in Chinese maybe better,because they maybe pushlish documents in chinese titles.

[Lakshmi]

Thanks much MrSun for linking.
By the way, my question was on SOM Module

[MrSun]

Thanks much MrSun for linking.
By the way, my question was on SOM Module

there are many references for rk3399 ,as far as i know they(Friendlyarm) will never share there pcb,some times you can search rk3399 in www.taobao.com,i think it's better then google ,at least in China.you can get many products about rk3399,such as roc-rk3399-pc,rock-960

[Lakshmi]

Thanks for your link.