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PX4 Hardware designs
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Settle on standard CAN transceiver #29

Closed LorenzMeier closed 8 years ago

LorenzMeier commented 8 years ago

We should identify the default part.

pkocmoud commented 8 years ago

When developing the CANESC 1.6 it was suggested that we choose a part which was ISO 11898-2 compliant. https://en.wikipedia.org/wiki/CAN_bus#Standards Therefore we settled on the Linear LTC2875 http://www.linear.com/product/LTC2875 . It seems to work fine.

nickarsov commented 8 years ago

Also a very good solution with best performance/price is TJA1051TK3/118 We use it in XRacer. Ben uses it in his ESCs.

LorenzMeier commented 8 years ago

@CarlOlsson Sounds like the TJA is your part then.

proficnc commented 8 years ago

Yes, this is the Transceiver that I am using....

On 24 Nov 2015, at 23:51, Nick Arsov notifications@github.com wrote:

Also a very good solution with best performance/price is TJA1051TK3/118

— Reply to this email directly or view it on GitHub.

CarlOlsson commented 8 years ago

Ok perfect! Thanks for the info

CarlOlsson commented 8 years ago

I cant find the TJA1051TK3/118 in the NXP eagle library or the pixhawk2.lbr or in https://github.com/pixhawk/Hardware/tree/master/eagle/libraries/eagle.

If I have not missed it I will create the part but where shall I add it to make it easier for future designers?

LorenzMeier commented 8 years ago

Pixhawk 2 libraries. The current generation boards are done in Altium.

CarlOlsson commented 8 years ago

Ok thx!

pavel-kirienko commented 8 years ago

TJA1051 is good, but in certain cases it is preferable to use a 3.3V transceiver. In this case I would recommend SN65HVD232 - it is cheap and automotive grade; the downside is that it's only available in SO8 which is huge.

LTC2875 Phillip mentioned is another 3.3V alternative in a small package, but its cost may be prohibitive.

proficnc commented 8 years ago

Agreed on the 3.3 vs 5v issue.

May I suggest that rather than trying to define a standard here... We just list devices that have been verified, with their strengths and weaknesses listed?

As long as they perform the job they are required to do, the choice should be up to the needs of the designer.

We should list some tests, ie, is it non blocking when a micro sets pins to locked values etc.... So maybe add a blacklist of parts that we will not accept if proven not to be up to standard

CarlOlsson commented 8 years ago

I agree. The reason to why I asked in the first place was that I wanted to use a design already proven to work. The list so far:

LorenzMeier commented 8 years ago

@CarlOlsson What was the final choice?

proficnc commented 8 years ago

The final choice was a whitelist and blacklist... As different components may suit different applications.

Anything that is deemed unsuitable should be blacklisted

nickarsov commented 8 years ago

To me, the white list currently looks like: TJA1051TK3/118 LTC2875

proficnc commented 8 years ago

Agreed

LorenzMeier commented 8 years ago

Thanks for the feedback Phil! I'll get that into the Dronecode wiki. What voltage (CAN bus, not their own supply) are these designed for - 3.3V?

proficnc commented 8 years ago

The Can side is always 5v, but the secondary on the TJA105 is 3.3v

Need to check the others

This is the one I am using now for all new designs

LorenzMeier commented 8 years ago

Noted here: https://wiki.dronecode.org/workgroup/connectors/start?&#can_tranceivers