As I was reading through the iCharging section of the tutorial, it said that in order to adapt the design to provide 2x 2.0V to the data lines they included 4 more resistors.
My question is- why can't you simply use a single voltage divider and connect the two pins to that 2.0V?
Thanks!
Is second voltage divider circuit necessary?
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- cadevon
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Is second voltage divider circuit necessary?
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- adafruit_support_bill
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Re: Is second voltage divider circuit necessary?
That would probably work. The current circuit was reverse engineered from a tear-down of an actual Apple charger. Some phones use different voltage on the two pins to signal other charging protocols.
- cadevon
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Re: Is second voltage divider circuit necessary?
So what configuration would allow or the most "generic" configuration? having 2.0V lines on the data pins (I assume so since thats how the project was designed and its widely compatible)
- adafruit_support_bill
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Re: Is second voltage divider circuit necessary?
Since the MintyBoost was released, the USB standards group has put out a standard for how chargers should work. And most of the industry is following it more-or-less. Apple phones and many others work with 2.0v on the data pins. Some phones work better if the two center pins are shorted together as well.
- cadevon
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- Joined: Mon Dec 29, 2014 11:13 am
Re: Is second voltage divider circuit necessary?
Ok great thanks for the answers!
Please be positive and constructive with your questions and comments.