Update:
It would be way better to start with a voltage that is closer to what we want, not 40v. It turns out it is not efficient to do that and maybe the reason the power supply we have are not doing the job. First test is to use the bench power supply to test that with 12volts 18volts and 24volts, that's the voltage of regular drill batteries. 18 or 12 would be perfect. Then how long will that battery power the doll.
codemonkeymichael
commented
1 year ago
Update: It would be way better to start with a voltage that is closer to what we want, not 40v. It turns out it is not efficient to do that and maybe the reason the power supply we have are not doing the job. First test is to use the bench power supply to test that with 12volts 18volts and 24volts, that's the voltage of regular drill batteries. 18 or 12 would be perfect. Then how long will that battery power the doll.
Need power supply that runs off 40 volt battery.
This will run the whole thing $235 3.3volt, 5volt, 12volt https://www.powerstream.com/DC-PC-5.htm
This is just enough for the pi $36 5volt https://www.digikey.com/en/products/detail/rohm-semiconductor/BD9G500EFJ-EVK-001/14003944