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javeryh's Woodgrain Cabaret Copy
javeryh:
Ok. The switches are wired for the volcano buttons. No issues (I hope). I am now finally ready to wire the LEDs... will this work?
The Trackball area on the iPAC2 has 4 pins. One is labeled 5V and one is GND. I have an extra cable laying around that I think could work:
As long as I keep the wires straight, is it OK to cut this wire in half and use one of the four wires for 5V and one other wire for GND both going to the LED? This would leave the wires labeled X1 and X2 to go nowhere...
Basically, I want to use this wire to connect to the iPAC2 because I don’t know how to do it otherwise. The connector would cover all 4 pins on the iPAC2 where it says Trackball but 2 of the wires would not be used. I’d splice in the resistor and the crimp connectors as originally planned on the other end.
Will this work?
Zebidee:
--- Quote from: javeryh on December 22, 2020, 05:15:35 pm ---Basically, I want to use this wire to connect to the iPAC2 because I don’t know how to do it otherwise. The connector would cover all 4 pins on the iPAC2 where it says Trackball but 2 of the wires would not be used. I’d splice in the resistor and the crimp connectors as originally planned on the other end.
Will this work?
--- End quote ---
I expect it to work fine given you're only drawing 40mA/100mW, which is comparable to what a trackball might draw so should be rated OK for that.
PL1:
--- Quote from: javeryh on December 22, 2020, 05:15:35 pm ---I am now finally ready to wire the LEDs... will this work?
--- End quote ---
Yes.
That type of connector usually mates with a polarized connector so you can't plug it in backward, but it should work perfectly fine on the IPac pins.
One thing that you might consider doing is if the 5v wire isn't red and/or isn't clearly visible, you might want to put a dot of red paint or fingernail polish on the connector housing by the 5v pin (or a green dot by ground) as a reminder which way the connector goes.
Scott
javeryh:
--- Quote from: Zebidee on December 22, 2020, 10:42:42 pm ---I expect it to work fine given you're only drawing 40mA/100mW, which is comparable to what a trackball might draw so should be rated OK for that.
--- End quote ---
--- Quote from: PL1 on December 23, 2020, 02:58:31 am ---Yes.
That type of connector usually mates with a polarized connector so you can't plug it in backward, but it should work perfectly fine on the IPac pins.
One thing that you might consider doing is if the 5v wire isn't red and/or isn't clearly visible, you might want to put a dot of red paint or fingernail polish on the connector housing by the 5v pin (or a green dot by ground) as a reminder which way the connector goes.
--- End quote ---
Thanks guys. One last thing... can I wire these two LEDs in parallel? So I'd only need one resistor. Go from iPAC2 GND to ground on BUTTON 1 to ground on BUTTON 2 and then from iPAC2 5V to 220 ohm resistor to + on BUTTON 1 to + on BUTTON 2. Or do I need to actually wire the + on BUTTON 1 and BUTTON 2 separately?
Like this...
PL1:
--- Quote from: javeryh on December 23, 2020, 04:21:20 pm ---can I wire these two LEDs in parallel? So I'd only need one resistor.
--- End quote ---
That configuration makes it a series-parallel circuit instead of two parallel circuits.
A guy on Stackexchange asked about a setup using one resistor to feed parallel LEDs.
https://electronics.stackexchange.com/questions/164370/9x-1w-leds-parallel-series-resistor-calculation-help-needed
--- Quote ---Manufacturing tolerances might make one LED draw a wide range of currents for a fixed voltage applied to its terminals. If you applied another LED in parallel one LED might take virtually all the current whilst the 2nd LED took virtually zero - this is the problem of not using a seperate resistor for each string of LEDs.
--- End quote ---
Best practice is to use one resistor per parallel branch so you get consistant current which will give you consistant brightness.
You can either wire it like below or daisy-chain one 5v line to the left side of the two resistors the same way you daisy-chain ground to the right side of the LEDs.
Scott