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2016年9月16日发售。型号有A1661,A1784和A1785,支持GSM 和 CDMA 格式,存储容量有32GB、128GB以及256GB,颜色有玫瑰金、金色、银色、黑色、新的亮黑和红色。

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Why CPU rails are shorted but phone still working fine?

I took 5 different iphone 7 plus and 2 iphone 7G and measure diode value on PP_GPU and PP_VAR_SOC but the value shows it shorted to ground. But what I wonder all the phones booted and booting normally with no overheat.

Can someone explain to me please

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hello John John microelectronic the best :-)

baby little boy, it’s not a short circuit- it’s low rezistance ;) but I laughed :) The link between processors, bucks and iCs is low voltage, for example 0.8V for iPhone. Additionally, poor meters do not recognize low resistance and treat everything as a short circuit, which is why you hear a beep. Look at the multimeter’s display - what do you see? Probably your meter is starting to squeak as low as 110 ohms. With such low parameters any resistance would be lethal to the signal.

You must a learn a lot of basic of electronic. Proper practice should be a buy a book (that normal one, traditional) and read about Ohm law, currents and voltages. That is basics. Buy a multimeter and read its instruction (papers) how to measurement. Than You will know that... low rezistant its not a short circuit. Don't watch youtube and ipadrehab anymore. You won't learn anything there, which would be valuable and necessary (but there are exceptions).

regards and fingers crossed

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I thought of it but I wanted to be sure for that.. thanks so much you helped a lot

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Learning basic electronics is good advice. Low resistance on a low voltage line makes sense if you understand what resistance is and how it affects voltage. However.

I still think watching YouTube is extremely helpful. It's not going to teach you everything, but I think it's an extremely valuable resource. I was watching an iPad rehab video literally TODAY where @jessabethany mentioned that these CPU rails often "troll" people due to their natural low resistance. In fact I find that many well known YouTube board repairers attempt to teach you to think critically about the mechanisms of the board and not just replace or remove components without a valid reason.

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hey Alisha, maybe I'm too critical but in my career most of the cases were something like this: "the rear camera does not work, tell me what I should to do, to work ... I replaced this element and soldered this cable to that something ... just like that guy on YouTube showed". The hands drop by themselves ... And yes, IpadRehab is an exception and Jessa has done a lot of good for the "fix it yourself" community. I respect and appreciate but, that what She shows - it's only a prelude to knowledge and being a microelectronics specialist. Maybe after training in ipadrehab ... :-)

- regards, and thank you for talking to Alisha, it's uplifting

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