RPi stepper driver and relay build log

Build Log
41

Here are some images of the traces. Trying to maximize copper going to the connectors.

First image is the view of all layers, followed by the front and back.

Thanks

Adam

routing_1.jpg929×548 119 KB

routing_2.jpg907×549 122 KB

routing_3.jpg841×576 111 KB

42

PCB rendering of the board! Some components are missing from the render.

saw_board.jpg1914×970 195 KB

1 Like
43

Just wondering about the pour and if I need to be concerned about regions where my voltage and current may be high. For example will it arc near the relays and some of the plugs? I’ve seen some cut outs on some boards and am wondering if that is used for electrical isolation? Any thoughts, critique

PCB-1.jpg1263×863 354 KB
or advice welcome!
Thanks Adam

1 Like
44

That render looks great!

What are the voltages you expect to see in the potential arc’ing area?

45

Thanks Chris!

I’m looking at 24V… for the most part. May like to switch some low amp 120V AC with the relays. The relays are rated to 10A.

On another note, not really sure how to design for copper pour (considerations). I’m looking into a few issues. For example if I get an island of copper where a trace is not grounded, can I place a trace to the ground pour?

Example in the attached image.

groudn issue.jpg1120×283 60.4 KB

All the best

Adam

46

Yes, you can manually connect those “islands” but it isn’t always required to do so.

I would also suggest taking a look at your spec’s on your copper pour, looks like the antipad clearance could be tighter.

47

Thanks Chris that worked !

48

New renderings. Started to use interactive routing - what a time saver! Also saw a good video on using global labels for marking pins so these labels can easily be changed to optimize routing. This made a big difference and will speed up future boards.

PCB-v2-Front.jpg1914×970 192 KB

2afc90a64d47bfe3fbefa2e92099a489fcbbaab3.png1914×970 108 KB

49

Hi Adam -
I think I win the “worst response time ever” badge. Sheesh. Sorry for not getting back with you - I (unknowingly) did not have email notifications turned on, and well, this got buried :frowning:

The Rhubarb is in early production. Retail price is ~$350. The link is not done yet, but the spec sheet is available here

In your follow-on post, you have the right idea. The RPi becomes the supervisory controller, the uC (Arduino, STM32, etc) becomes the realtime controller. This is what the Beaglebone series of SBCs do.

Also, the board looks great :slight_smile: How did it work out?

50

Hi John,

Thanks for the response. It worked out well thanks.

All the best,

Adam

1 Like