Quote:
Originally Posted by asid61
As a side note, EAGLE does have an "LED" part in the default libraries, so you don't need to use a diode. Also, try using 2.2k resistors for your leds intsead of 100 ohm. 100s will probably cause too much current for the led, and 2.2k makes it plenty bright for indication purposes.
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I'm actually using the sparkfun libraries for the 0603 LED (0603 because I have them on hand). I did the calcs for the LEDs and, if I'm remembering properly, 100 ohm is what I worked out for about 10 mA for a series 3.3v drop across both the LED and resistor. The actual LEDs I'm using are specced at 25mA. I figure if I can go bright I might as well, the more flashing LEDs in a robot makes it look more sciencey. I'll look into dropping the current a bit more though.
Quote:
Originally Posted by asid61
I love the limit switch LEDs.
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Thanks!
Quote:
Originally Posted by asid61
Optional pullup resistors are great. You might want to try one of those header bridge thingies to switch between 5v and 3.3v (possibly also for the pullup resistors). Solder bridges make it hard to change without a lot of hassle.
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I wanted to go the solder bridge route because I figured that it's free, no jumpers to lose, our team only uses one kind of encoder (so we just set the voltage and don't ever need to change it), and anything that sticks up off the board is liable to get smashed and bent when stuck into some drawer somewhere.
Quote:
Originally Posted by asid61
Use the "smash" tool to separate names and values of components on the board. That lets you put the names where you want them most visible, and you can delete that values; those don't need to be on the board.
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I smashed most of the components, the label positioning you see is pretty much the best configuration I could figure out, given vias and stop mask and components.
Quote:
Originally Posted by asid61
Have you tried pricing this out on Digikey?
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I did a BOM for all the components on mouser and am looking at somewhere around $2.5 dollars in components per board, the biggest ticket item being the .05" header, at ~$0.8. Via OSHPark, each board is about $2. I figure this seems reasonable, considering the SRX breakout on andymark is $15, what with having to make money and all.