Released June 2012 / Core i7 processor with Turbo Boost / Up to 1 GB DDR5 Video RAM

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Need help identifying missing components from logic board for USB

I have a macbook pro 15" a1286 with the 661-6492 logic board. Its the mid 2012 non retina i7 model. I was doing a repair on the keyboard and it seems that unfortunately two components broke off the board adjacent to the usb ports. These two components clearly have something to do with the USB ports as they both no longer function. I am fairly certain these are the only two components needing replacement, and I can see the pads have not been ripped off just the components.

From pics I found of these logic boards one looks to be a diode (it was all black so could be a resistor too however it was pretty big) and has two legs whereas the other has four and is most likely an IC or transistor.

I am a EE and have all kinds of soldering/reflow equipment, but its useless without knowing what the components are. I have been scouring the internet for the schematic but all the sites I've found that have it want money for it. Any help is greatly appreciated.

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Charlie W, "one looks to be a diode (it was all black so could be a resistor too" neither nor:-) This is just to answer your question about the components, not to diagnose your board.

Reference designator L4605 is a 120 Ohm-3A filter in a 0603 package

Reference designator L4700 is a 90 Ohm-100MA DLP11S common mode choke

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Just curious, do you know whether or not I can just jump these connections with a 0 ohm 0603 resistor?

I am going to order the chips anyways from Digikey, and they have a direct replacement for L4605 but for L4700 they only have a 90 ohm 150MA DLP11s choke. Correct me if I'm wrong, but I assume the current rating of 150ma is not an issue, as it would only be an issue if it were <100ma.

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You are correct with the L4700 and should be okay with the MA. I've never been a big friend of using jumpers across filters and inductors but I guess you can always give it a try.

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Ok so Digikey has two versions of the 90 ohm 150ma DLP11S choke.

One is for high speed differential signal lines and one is for ultra high speed differential signal lines.

I would think USB 2.0 would be fine with the high speed versus ultra high speed. According to the data sheet the high speed one is good for several hundred MHz and afaik usb 2.0 is max 48Mhz.

The high speed one is part number DLP11SN900HL2L and ultra is DLP11SA900HL2L

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Go with the SN900

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Replaced the two components and both USB are functional again! That choke sure was hard to solder on glad I ordered 10...

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Charlie W will be eternally grateful.
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