Control a light array with external power source via Raspberry Pi

I would like some advice on what products I could use for a particular project.

I want to create a portable system including a Raspberry Pi 3 B that can control an external light array. The Pi also needs to work with an NFC reader with other sensors (I’m using a Sense Pi HAT right now for that).

I have successfully used an NPN transistor with some resisters and an external 9v battery power pack to turn on an off an array of small LEDs with a GPIO pin on the Raspberry Pi.

Having two seperate power supplies is not ideal however. Since setting up the Core Electronics 7" touchscreen which has a Micro USB Splitter Cable, I realized that I may be able to use something like this with a Lipo battery and the Pimoroni Zero LiPo Core sells.

It says that it will work with a Raspberry Pi 3 B also. What kind of Lipo would I need to power the Pi with the 7" screen and an array of lights like the 5M RGB LED Strip - WS2812 60 Per Meter - Black Strip - Weatherproof that is used in the infinity mirror project on your site? In that project you use a Particle Photon with a plug in power supply.

Can anyone tell me if I can use the Pimoroni Zero LiPo to do what I want? Also, what kind of Lipo battery would I need for the Pi, the NFC reader, the screen, etc? And, since I’m not great with my Ohms Law calculations, what kind of resisters would I need to protect the Pi from the lights array?

I have followed Peter Bennetts answer to this question as a guide so far:

Any suggestions/advice would be greatly appreciated.

1 Like