4 AA batteries + LM7805 regulator (USB charger)?
I'm wanting to make a project which I take a 4 pack of AA batteries and use them to charge USB. I'm going to put this in an Altoids box (because I can. And so I did a LOTT of research the past few days.So, I got 6v with the 4 batteries, and a USB outputs 5v DC. So I need a regulator (LM 7805) to bring it down. But I also heard that USB also outputs 2v to tell the charging device (like an iPhone) that it's really a charger and someone's not hacking/modding like me. That's my question. I've heard that I need 2 22k ohm resistors and 2 33k. Where does that all get put into play? Anyone in electronics can help me?
LM7805 does not work on 6V power source.
- Why is Apple so keen to push USB-C with their Macbooks but they don't include USB-C on the iPhone? It seems like the Macbook department at Apple thinks USB Type C is the best thing since sliced bread but the iPhone department thinks USB Type C is work of the devil.
- Voltage regulator VS voltage divider? I want to make a few of those altoids oh sh*t USB chargers. Instead of using the 5V regulators like everyone else does, can't I just create a voltage divider with two resistors? Why though? As long as my Iphone is seeing 5V it shouldn't matter, no? Or is the regulator really some kind of current regular aging device too? Dun think so. And what are the odds of me destroying my cell phone? You think there's circuitry protection of I screw up the polarity?
- How to put new batteries in your iPhone 4S? For my birthday, my 24 year old daughter Rebecca bought me an iPhone 4S. It says that it has very low battery, and I can't figure out where to buy batteries for it! Also, I can't seem to find a place where the iPhone can open. Anybody know where to buy iPhone batteries?
- How are the Iphone batteries different? I have a iphone 2g and I'm going to mod it so I can get the 4S operating system. But I'm afraid that it will drain the battery. How does the iphone 2g battery differ from the others