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[Q] Cover with micro-sd slot

OP sautzer

21st January 2014, 12:17 PM   |  #1  
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I'm looking for a cover with microsd slot but I haven't found nothing. So I want to know if there are problem to make a thing like this or nobody hasn't thinked about it. I think that make it is possible because there are some OTG that read microsd(I have it) but with it I can't charge the phone and I'm afraid of break it when it is in my pants. I've thinked to make a cover with microsd slot and external battery(like the image below), it is possible?
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22nd January 2014, 07:55 AM   |  #2  
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The pin you marked with <?> is the key to USB OTG. In order for your stick/card to work, you'd have to connect that pin to ground. Then, when you wanna charge/access the phone (from a computer), you'd need to disconnect that pin.
The main problem that I see is that there isn't enough space between the original cover and the phone/battery. The second problem is that our beloved Nexus is old and many thinkers moved away to newer devices. And, to access the USB port internally, you'd have to open the phone, which would void the warranty (if the phone still has one).

PS: Still remembering those kind of math exercises from high-school :P
27th January 2014, 10:33 AM   |  #3  
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Why i need to disconnect the key to USB OTG when it is charging? If I'm right to charge the phone we only use the 5v and ground pin. I've thinked about create a cover like the picture below with the micro sd slot, so without opening the device. Hope that you can help me again
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27th January 2014, 05:52 PM   |  #4  
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To put it simple when you use a OTG device (like a card reader) your phone powers the card reader (electricity flows from phone to device). When you connect your phone to a computer/charger the device will charge your phone (electricity flows from device to phone). This functionality is controlled by connecting pin 4 of the microUSB maje jack to ground. I've read that some Xperia phones have a 3rd option: if you connect a certain value resistor between pin 4 and ground, you could power both the phone and the card reader from your charger.
Cheers!
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