Repair guides and support for 21.5" Intel iMacs by Apple.

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Help to identify tiny 4 pin chip on motherboard of iMac a1224

Hello i am trying to repair an Imac with lightning damage. The model number is A1224 which is a 20" screen model.

unidentified chips circled in red

I would like to identify the chips circled in red.

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I suspect these chips are leabelled by FL9400, R9400 and R9410 on the PCB and may be related to that Delta ethernet transformer LFE9287.

I have already found out that the other blown chips '0524P' are diode arrays manufactured by Bourns part number CDDFN10-0524P.

The overall location of these chips is just above + to the right of the right RAM slot see picture in step 9:

iMac Intel 20" EMC 2266 Logic Board Replacement

So far i think they might be some sort of common mode choke but i would love a link/part number so i can source replacements. It was lightning damage and i have tested PSU unsoldered mosfets, caps etc ad tested with multimeter and t is working to spec now i try to fix the motherboard.

thanks in advance.

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SAMZOR, from the schematic R9400 and R9410 are "No Stuff". This means that they are not going to be assembled during the assembly. The reference designator is a location provided as a optional or feature specific needs demands. All your components look identical. They all seem to have 4 solder points which would make them not resistors. The bottom component looks like it split in half and flipped over. Hard to see on a picture. You may have to verify that closer. The components are all common mode filter chokes, FL9400, FL9401 and FL9402. All listed chokes are 12ohm TCM1210-4SM. You are correct about D9410 being a diode array. The original is a Semtech SLP2510P8, similar to the one you listed from Bourn but slightly higher values.

Hope my added image makes sense.

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