Wednesday, June 5, 2013

Dual Motor Cape Version 4 is in!!

I'm using the Silhouette Cameo Stencil cutting technique I found from  The results were good enough to use:
Minor variations I found was that I had to set the physical cutter depth to 3 instead of 1 as indicated in Cathy Saxon's article.

Populating the board (except for missing J4, still in transit from Mouser):

One of the things you'll notice that I've changed is the motor and power connectors.  I've using Molex Microfit connectors, instead of the screw terminals.  The reason for the change is that I felt that using the screw terminals might be unreliable when using this board on a mobile robot.  The only downside is that the Microfit connectors are rated at 5A max.  I think I will have to leave it at that spec when I sell the boards (although you could always solder wires directly to the board to get a higher current -- the ST Micro HBridge chips are rated for up to 30A if you add a few heat sinks in).  I'll probably keep the spec at 5A continuous, and 10A peak (violating the Microfit spec a bit -- they do spec the two circuit connector at 7A, but I want a little leeway).