Cutting Teensy 3.6 down to size?

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dukeblue219

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I have some existing projects that use a Teensy 3.1/3.2, but could use the features (speed in particular) of the 3.6. Electrically I could drop in a 3.6 just fine I believe, but without redesigning the PCB it cannot physically fit without the SD slot overlapping another component (which I cannot do). If I cut through the row of thru-holes between the SD slot and the pushbutton it would fit. Any show-stopping reason I cannot do this? Of course, yield might not be 100% and some cleanup might be necessary to avoid shorts, but this isn't a production system or anything.

Thanks!
 
Looking at the PCB I can see that the Reset line, Prog Line and VBat line are routed outside (on the SD side) of those pins. So cutting along those pins would I suspect disable those lines. Now if anything is feeding from that then it might disable the programming capability. Probably better off cutting between 28 and 37. But without the PCB Gerber's it's quite hard to tell.

I would defer to Paul for a definitive answer.
 
Teensy 3.6 is a 6 layer PCB, with ground plane on layer 2 and power plane on layer 5. Any cutting should be done carefully to avoid shorting these layers.
 
Thank you both. I'll give it a shot then. It'd be nice to avoid re-spinning the boards I plug the Teensy into until our next planned revision.
 
Can you show us a picture of how the Teensy is mounted? I'd like to see what is in the way and how tall is it?
 
Can you show us a picture of how the Teensy is mounted? I'd like to see what is in the way and how tall is it?

It's not that a tall object is in the way so much as we need line of sight from directly above the component that would be shadowed by the Teensy 3.6. I can't publicly post pictures of the board involved unfortunately.
 
Teensy 3.6 is a 6 layer PCB, with ground plane on layer 2 and power plane on layer 5. Any cutting should be done carefully to avoid shorting these layers.

Is this the same for 3.2? I usually would trim the edges of 3.0 and 3.1 and it would still work. I trimmed the 3.2 edge and it will not work. I can't figure out why because I don't see anything related to the power or ground on the pins that would stop it from working.
 
Is this the same for 3.2? I usually would trim the edges of 3.0 and 3.1 and it would still work.

Check if VIN power is making it to the fuse & regulator.

Otherwise, it should be pretty much the same as 3.1. All of them are 4 layer with a ground plane on layer 2, so you should always have some concern about shorting things to ground if the cut isn't perfect.
 
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