Hello, I am trying to make a small portable wearable, i am still in the just trying it to work phase, but I am starting to realize my initial idea for power might be to clunky in the end. so essentially I'm just looking for any ideas of how I could "condense" my power supply to maybe a single battery or battery pack. currently I have an EMG sensor connected to a Nano Every both of which are powered from my laptop via the micro usb port, the goal is to add a micro servo to the nano. I power the servo with a 3.7V Li-ion battery. with this layout I would have two batteries. would it be possible to use, for example a 9 V, battery and resistors to power everything? I am still very new to electronics and circuitry, so any advise is appreciated.
No. You can use SMPS (Switch Mode Power Supplies) buck boost whatever fits. The resistors are a disaster, as the current changes the voltage will also change.
What voltage(s) do you need? At what currents?
Please post a wiring diagram with references to what you actually are using.
To add to what @gilshultz wrote. See the application don'ts on this page. Voltage Dividers - SparkFun Learn.
The EMG I am using is the bio amp candy by upside down labs, with an input voltage of 3.3V - 30V,
Bio amp candy
the micro servo i am using has an operating voltage of 3.0V - 6.0V, and the Nano has operating voltage of 5v.
How much is the average current draw while the circuit is operating? You need to know that to be able to size the battery capacity. Then you can know how often charge is required.
So everything will run from 5V, A small LiPo (if capacity enough) and a boost converter/charger to 5V may handle what you need.
I don't yet know what the average current is, but I should be able to figure that out soon. Hopefully the materials you linked will work, the size would work perfectly.
I now have access to a multimeter I have been able to get accurate volage readings but I have not been able to get anything for current. Any suggestions would be very helpful.
it took me a bit but I finally was able to get the current. the servo reaches a max of 250 ma, the nano with the muscle sensor is much lower at 0.034 a.