Inside is a 5000mAh lithium ion battery and boost converters that provides two USB A ports with 5VDC up to 2.1 Amps. Great for single board computers like Raspberry Pi
The charging circuit will draw 2A from a 5V supply (plug a microUSB connector into the pack and then to a computer or wall adapter). You can charge and power something at the same time but there’s ~80% efficiency loss on both ends so if you charge it at 1A and draw 1A at the same time, the battery pack will eventually go empty. However, if you’re powering something that’s 500mA or less, you can keep it topped up no problem. Also, when you start and stop charging the pack, it will flicker the output, this can cause a ‘power sensitive’ device like the Pi or an iPhone to reset on the power supply. If using it with a low current load, say under 100mA, the pack may ‘fall asleep’ – you can use this circuit to keep the pack awake
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.