Ok, i had this cool looking tri color AA battery powered lava lamp lying around. I love this lamp cause it was a wifie gift before we got married
I had it packed away cause i think i got tired of it eating my AA like it was junk food. I had resently found it when i was dong a clean up "Cause im such a packrat" (wifie quote)
i didnt want to throw it away cause it is awesome, tri color LED/ oil lamp. But i hate hate hate hate! buying giant packs of battery and throwing the spent once away after it just ate it up after 8 hour of use. Its just bad for the enviorment wasting so much battery. AND yes i have bought rechargeable kinds but again it eats it up every 8 hours of use and charging takes 8 to 12 hours..running back and forth from charger to lamp to keep it going is to much hassle.
Ive deside to go ahead and mod the lamp to run on USB power so i can also adapt it to solar power
issue being i face is i know the lamp needs 3 AA to run..which each battery is about 1.2 or 1.5volts ... and USB pumps out 5 volts ..mathmaticly (1.2*3=3.6volts needed) so i need to drop the amount of voltage to a safe level of 3.6 maybe less to reduce blown outs...but i dont know how many milliamps the USB port oushes off
so i want to make sure i dont kill the mini 555 chip on the board i need to calculate the right amount of current.
then i need to figure out what kind of resistor to buy and solder it to the switch
Does anyone know how do i do that? i know so much but dont have training in anything further DX