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Schwizzle
10-23-2017, 05:36 AM
Greetings. There is a question I haven't been able to find an answer to, clearly at least.

On page 39 of the manual, it says that the Power-On Indicator pad is "a regulated 3.3V pad". That should mean that it doesn't need a resistor right, same as the channel 1/main LED pad.

However, he still shows a resistor being used, so checking to be sure. If a resistor does need to be used, is anyone aware of the current for the pad? I would like to think it is the same as the other accent LED pads (18ma).

Thank you kindly.

Forgetful Jedi Knight
10-24-2017, 07:29 AM
It would need a resistor, depending on the voltage of the LED you are attaching to it. If you are attaching a 3.3- ish V LED, then no, you wouldn’t need one. If you are attaching a 2V LED, then yes, you’ll need one. The pad’s current is 18mA.

Schwizzle
10-24-2017, 08:18 AM
It would need a resistor, depending on the voltage of the LED you are attaching to it. If you are attaching a 3.3- ish V LED, then no, you wouldn’t need one. If you are attaching a 2V LED, then yes, you’ll need one. The pad’s current is 18mA.

Thanks. I'm doing a green momentary switch and a purple momentary switch, both are 3.0 volts. Technically, I would need an 18ohm, 1/8W resistor. Think I could get away without them though?

My local electronics store has 18ohm 1/4 watt resistors. The wattage would be overkill, but shouldn't affect brightness I believe.

Forgetful Jedi Knight
10-24-2017, 08:28 AM
I'd use a resistor for each one. They're cheaper than replacing the switches. ;)

Schwizzle
10-24-2017, 08:42 AM
I'd use a resistor for each one. They're cheaper than replacing the switches. ;)

Yep, and less time consuming as well. I'm not going to use JST connectors to try and save space, so I would have to cut wires, resolder, whole lotta ugh.