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9v to 3v "easy button" hack.

Hello!
Im working on a Staples Button Hack! but.....
Problem that I have is that I feel like it is a Waste to scrap the original "that was easy" message. And the problem that comes along with this would be that I have to use a 9v battery to power the new circuit and the original button circuit uses a 3v battery.
I'm not great with Ohms law but I do relize that I need a resistor but... i do not know if that will put in too much current into the original circuit?Would anyone know how I can calculate this? And does the amount of current even matter?

-Thanks!
Noobiefied

aelias365 years ago
Try reading this:
https://www.instructables.com/answers/How-much-resistance/
I'd use a small voltage regulator. There are regulators that have only 3 terminals: input, ground, and output. The only other parts they require to operate properly are a couple capacitors for the input and output, which the datasheet for the regulator will suggest.

The regulator will produce a constant 3V output, regardless of the load. Make sure you select one that can handle the current your circuit needs, which is most likely very low.

All the part required should be less than a couple dollars total from a source like DigiKey.