I would like to design a “pass through” charger with optional solar input for 4 18650 cells. The load will be a raspberry Pi with some number of USB connections.
-If external power is connected, battery should continue to charge while powering the load
-If external power is disconnected, it should switch to battery power without current or voltage drop.
What IC/devkits should I look at? Max budget is about $50.
Many thanks in advance
Welcome to the forum.
The Waveshare Raspberry Pi UPS HAT has schematics and IC data sheets for their design on their Wiki.
I tend to just buy low end APC & CyberPower UPS’s designed to run a high power PC and use them for multiple Pi’s to save money.
If I needed to save space, I’d try out the Waveshare product.
There are many discussions of this topic at the Raspberry Pi forum.
I looked into this. For a variety of reasons, I’m not really interested in a hat.
Furthermore, I recently purchased from WaveShare. My experience was not positive.
However, I will review their wiki to see if I can find anything else useful.
How much wattage do you need?
These are fun to play with: https://www.digikey.com/en/products/detail/dfrobot/DFR0535/9330116
More info: "Solar Power Manager
Yeah, I remember these guys. They are pretty awesome, I’m glad they made it to DigiKey. Not sure it will work in my application, will read more.
Thanks so much!