Author Topic: What's the L pad?  (Read 1478 times)

taeagan

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What's the L pad?
« on: February 06, 2016, 08:43:38 PM »
So I ordered a bunch of madbean boards and I've been trying to do my homework before I get too far into soldering stuff up.  What's the L pad on all of the board that seems to be tied to the LED neg. pad?  Most of the boards seem to have the same G, L, LED +/-, I, O layout for the off-board wires.  But L and LED neg. seem redundant to me.  Any help?

Leevibe

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Re: What's the L pad?
« Reply #1 on: February 06, 2016, 09:02:15 PM »
It wires to the third pole of the stomp switch to switch the indicator LED on and off. Check out the standard wiring diagram on the projects page.

kgull

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Re: What's the L pad?
« Reply #2 on: February 06, 2016, 09:36:58 PM »
L and LED neg. seem redundant to me.
You are correct.

It's mainly a pair of 'courtesy pads' so that you don't have to hang your LED off of the stomp switch. Makes putting stuff together less of a chore.

taeagan

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Re: What's the L pad?
« Reply #3 on: February 06, 2016, 09:44:24 PM »
Thanks.  Just a heads up, I don't see a link to a Standard Wiring Diagram on the Projects page.  When I googlize "standard wiring diagram site:madbeanpedals.com" it links me to this pdf, but this seems to be outdated because it has battery snaps, has the 4.7k resistor off board, and doesn't mention the L pad:

http://www.madbeanpedals.com/tutorials/downloads/StandardWiring_MBP.pdf



kgull

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Re: What's the L pad?
« Reply #4 on: February 06, 2016, 09:57:35 PM »
Yeah, looks like the bean has been doing some site upgrades, I can't find the diagram I was thinking of but the basic idea is that you short the "L pad" (called the "SW pad" on some newer boards) to ground whenever you want the LED to light up.

Go with your gut and if that doesn't work post some photos once it's built and we can point you in the right direction. Actually post some photos in a build report anyway. We like ogling :P

Jebus

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Re: What's the L pad?
« Reply #5 on: February 07, 2016, 10:53:17 AM »
Thanks.  Just a heads up, I don't see a link to a Standard Wiring Diagram on the Projects page.

Its been moved to Tutorials -section: http://www.madbeanpedals.com/tutorials/index.html

taeagan

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Re: What's the L pad?
« Reply #6 on: February 09, 2016, 03:19:26 PM »
So in the footswitch wiring diagram there's a gray wire going from the led to the footswitch. So I'm guessing that on the board layout the intention is for the led to get wired to led- and for the switch to get wired to pad L. Right?

m-Kresol

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Re: What's the L pad?
« Reply #7 on: February 09, 2016, 04:09:08 PM »
correct.
the + and - pad of the led are next to each other so you can board mount it if desired. then you'd jsut have to connect the wire from the L pad. If you're not gonna board mount it anyways you can also run the wire directl from the led's cathode.
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