iPhone 4s motherboard part name its a small chip

Jay, that is reference designator U3_RF which is a RF1642 BROADBAND HIGH POWER SP4T SWITCH Package Style: QFN. from the image it looks like a 3x3 package. RF1642 is most likely manufactured by RFMD but I can not find a datasheet on it. Hope this helps, good luck.

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ok one question: if i remove this U3_RF and bypass ground and main line to ahead then what happen,is it work? I allready bypass U17_RF and work.

Sep 1, 2014 by Jay

Jay, If you bypass U17_RF, you will also have to bridge HB/LB connection with GPS/GNSS, otherwise you lose the diversity antenna or GPS antenna, depending which connection you forget.

U3_RF is the primary/diversity antenna switch, iPhone 4s use this switch to switch the Tx signal between 2 antennas. If you bypass this switch, you will lose Tx on diversity antenna, which can cause the "death grip on iPhone 4 to happen on your phone.

if you are OK with that, it should work without other problems.

Sep 1, 2014 by Tom Chai

Oh yes Tom diversity and gps not working due to U17_RF bypass, but ok.Now I planning to bypass U3_RF because I getting network problems like searching or no service.One important thing is when i check blue coil(L47_RF) line and ground line by digital meter, its sounds beeppp,means something short.How can I determine U3_RF working or gone short?

Well ,Thanks Tom for nice discuss.:-)

I also want to thanks oldturkey03.:-)

Sep 1, 2014 by Jay

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ok one question: if i remove this U3_RF and bypass ground and main line to ahead then what happen,is it work? I allready bypass U17_RF and work. — Jay
Jay, If you bypass U17_RF, you will also have to bridge HB/LB connection with GPS/GNSS, otherwise you lose the diversity antenna or GPS antenna, depending which connection you forget.

U3_RF is the primary/diversity antenna switch, iPhone 4s use this switch to switch the Tx signal between 2 antennas. If you bypass this switch, you will lose Tx on diversity antenna, which can cause the "death grip on iPhone 4 to happen on your phone.

if you are OK with that, it should work without other problems. — Tom Chai
Oh yes Tom diversity and gps not working due to U17_RF bypass, but ok.Now I planning to bypass U3_RF because I getting network problems like searching or no service.One important thing is when i check blue coil(L47_RF) line and ground line by digital meter, its sounds beeppp,means something short.How can I determine U3_RF working or gone short?

Well ,Thanks Tom for nice discuss.:-)

I also want to thanks oldturkey03.:-) — Jay

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iPhone 4s motherboard part name its a small chip

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