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Why is my portable charger doing this. Answered

Okay so everything is solderded correctly with the right amount of voltage on the data lines. When i check the voltage it says 6.54 but when i plug my usb up to my phone it drops to 2.89 why is this? I used this https://www.instructables.com/id/Make-a-USB-iPhone-iPod-Charger-On-The-Cheep



Best Answer 5 years ago

You have a mistake on your 7805 regulator pins.
The unconnected output voltage MUST read 5 VDC
even before connecting up the iPhone...


the outuput is reading 5v but its like when a load is put on it thats when the voltage drops to 2v my other charger was built successful

Insufficient Battery
Like Steve said Dec 12

yea ima try a duracell or energizer battery instead of these cheap dollar store ones

Once again, a 9V rectangular battery is going to really struggle to drive anything LIKE charging current for a USB charger.


9v batteries are garbage except for very low drain 'higher' voltage applications - like smoke detectors. Everywhere else they are a waste.