I do understand that similar questions and maybe even the same question has been asked before, I've found them but unfortunately as a result of inexperience on my part I have been unable to adapt the posted solutions to my design specifically.
I am currently working to build the power side of my overall circuit that uses an 18650 (3.7v, 2600mAh) battery that is charged through an MCP73833 IC. The source power for charging will be a 5V wall wart power supply. What I am trying to accomplish now is to create a path or switch that disconnects the battery when the 5V power supply is connected, while preferably allowing the the 5V to be used to power the project and charge the battery at the same time.
Based on prior answers here on EE, I've heard that two Schottky diodes can be used with a little forward voltage drop; I've also seen recommendations for FET's. I'm trying not to add any more IC's to the project if I do not need too especially since I'm hand soldering all of this (not meaning FET's, but actual IC's).
Forward voltage drop is not critical since I'll need to step-up the battery voltage anyway after this circuit (to 5V for MAX7219). So it wouldn't be a big deal to run both power sources through the same booster.
My problem is that I have zero experience with Schottky diodes and even less with Mosfets. I've been reading and trying to understand but just when I think I do, I look at my circuit and my brain turns to mush.
Obviously if you see any errors within the circuit and wouldn't mind pointing them out, I'd appreciate that as well.
Answer
Microchip's AN1149, "Design A Load Sharing System Power Path Management with Microchip's Stand-Alone Li-Ion Battery Charger", describes how to use 3 components to allow switching between off-line and on-line operation without interruption of power.
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