Project Details:
So Im making my first DIY Arduino using an Atmega328
Will control two 3W high powered RGB LEDs
I also have a constant current led driver for them
One 12V white led halo ring
One Bluetooth Module
I'm transferring the circuit I have on my Arduino Uno to a perfboard. I've done everything to get the chip working, now I need to bring down one of the 5V pins to 3.3V for the Bluetooth module I have, that takes 3.3V. The correct resistor would be 125 ohms, but the closest I have is a 150 ohm. I also have a really small pot set to 125ohms and one of the larger pots set to 125ohms. I looked, but I dont have a LM317.
A few questions:
1) Which would be the best way to go, the 150ohm resistor?
2) Will those extra 25ohms make a big difference in output voltage?(If Im doing the math correct, to get an output of 3.3V with a 150ohm resistor, the arduino pin would have to output 22mA, which it's safely capable of)
3) Or would using the pot at the 125ohms be better?
4) Also, I have the small pot(100k), size of a dime. Then I have one of the bigger pots(25K). Whats the difference? Obviously putting the smaller pot on the perfboard would be much easier than trying to fit that big one on there, but thought I'd ask to make sure.
Any help appreciated. Thanks
So Im making my first DIY Arduino using an Atmega328
Will control two 3W high powered RGB LEDs
I also have a constant current led driver for them
One 12V white led halo ring
One Bluetooth Module
I'm transferring the circuit I have on my Arduino Uno to a perfboard. I've done everything to get the chip working, now I need to bring down one of the 5V pins to 3.3V for the Bluetooth module I have, that takes 3.3V. The correct resistor would be 125 ohms, but the closest I have is a 150 ohm. I also have a really small pot set to 125ohms and one of the larger pots set to 125ohms. I looked, but I dont have a LM317.
A few questions:
1) Which would be the best way to go, the 150ohm resistor?
2) Will those extra 25ohms make a big difference in output voltage?(If Im doing the math correct, to get an output of 3.3V with a 150ohm resistor, the arduino pin would have to output 22mA, which it's safely capable of)
3) Or would using the pot at the 125ohms be better?
4) Also, I have the small pot(100k), size of a dime. Then I have one of the bigger pots(25K). Whats the difference? Obviously putting the smaller pot on the perfboard would be much easier than trying to fit that big one on there, but thought I'd ask to make sure.
Any help appreciated. Thanks