7-19 volt Universal AC/DC lights are already set up "plug and play" for your own power supply
How many can run at once?
Using a 3 volt coin holder you can run 1-10 chips.
Using a 3 volt AAA holder you can run 1-30 chips
Using a 9 volt battery snap/switch you can run 1-50 of the chips.
Using a 12 volt 1 Amp supply is also 50 chips, no need to turn off.
Using your own power?
The chips draw 20 milliamps each. So check your power supply to see how many milliamps it lists. A 1000 milliamp supply can run 50 chips.
can the chip LEDs be run along with other LEDs from the same battery or coin cell?
Yes the chips can be run right alongside the other sizes of LEDs on the same power supply.
