XCore Exchange

Hi,

Second post for today ...

I am looking for a reference design dedicated to the XS1-L4A-64-TQ48-C4. Has anyone such a design, please ? I found this thread which is very interesting : http://www.xcore.com/viewtopic.php?f=21 ... XS1+L4A+64

I am designing a custom board based on an application prototyped with the startkit but I want to make sure that I do not make any mistake ...

Thanks,
Best regards,
Nicolas

Hi Nicolas. I think a good idea is to request you to post your schematic for a review and comments from other developers. It is far too easy to forget a small detail and then have to rework boards which can get expensive. Which CAD tool are you using ?

Hi Mon2,
Thanks for your reply.
At the moment the schematic is not done. I am trying to evaluate the complete BOM of the project.
I will use Eagle but I may not be able to post the schematic for confidentiality reasons.

You should be able to extract all the juicy details from the user forum but pay attention to:

a) current draw for the respective power rails - be sure that your power rails can offer the required current for your project. More cores in use = more power required.
b) the power on reset and power sequencing order and delays are important. Many outputs of such devices are open drain so do not forget the pull-ups
c) if using USB, be sure to apply some in-line polymer fuse (most are $0.10 USD or less now) or a USB load switch which offers in rush current, reverse protection, current limit
d) apply ESD protection onto the USB interface - mandatory if you want the product to have a nice field life
e) on crystal costs, a crystal of this value should be $0.06 to $ 0.10 USD (max) - you can source from WTL.

On the topic of costs, the crystal is available for about $ 0.06 USD from Shenzhen, China

< you can also order through their Aliexpress store >

Valerie
Account Manager
WTL Interantional Limited
Email: wtl001@wtlcrytals.com
Skype: wtl-delly
Whatsapp & Wechat：+86 159 9962 7016
Tel:86-755-82677582-801

Chime back if you need help on the hardware details or parts sourcing.

Thanks for the sourcing details.
Where do you source XMOS parts ? I am looking for the cheapest way to get a 4 core devices (or 8 cores, XS1 or XS2). I am also looking for a XCore-200 (XU or XE 216) ...

For us, we found Future Electronics to be the most competitive. Build up a case with desired targets and potential volumes. XMOS can be aggressive on costs through distribution. Alternatively you can try Asia as there are many XMOS based designs out of China. Digikey is great for immediate stock but usually at a premium cost.

Ok thanks !