hello everyone, I have a problem with my macbookpro 2017 820-00928, it's stuck at 20v 0.20ma, the indication of heat on the U8295 ic on the PP3V_S0_LEFT line, I've removed the ic and I shoot the voltage but there is no indication of heat in other areas, these are all rails except Vcore cpu..what should I explore next,,thanks
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Re: a1707 820-00928
Hi. Try to avoid voltage injection till more is known about the logic board. Otherwise, this can cause permanent damage to the circuit board.
With U8295 removed, place your meter in resistance mode (2k scale). Remove all power.
Check the resistance to ground of pins 3 and 5 of U8295 pads. Something is causing this part to heat up and could be an excessive load on the rail.
Post the readings. -
Re: a1707 820-00928
stil short reistence in pins 5 of U8295 after i remove ic.just info all rails in u8925 present especiali pads no 5-6 still short...anyway voltage PP5V_S4_X_USBC not present..Comment
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Mounting and Handling Guidelines for TO220 TO220F TO247 Cases / Packages
The TO220, TO220F and TO247 are the popular packages for power devices because of their versatility and ability to dissipate moderate amounts of heat. This application note describes the basic guidelines for handling power MOSFETs in TO220, TO220 and TO247 packages shown in Figure 1. Please note that only mechanical and soldering guidelines are covered here. Additional precautions are required for isolating high voltage rated devices to meet safety regulations.
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My question is if this IC can be ordered from Aliexpress (will it work) ?? or it needs to be taken directly from donor (a1707, a1990, a2141) ?
Is this IC interchangeable (on my board i have 6142E and i found that there can be also HD3SS212) are this chips same ? ? Is it possible to find this IC on some other Macbook 13" (air, pro) ?? i have...04-25-2025, 07:55 AM -
detecting heat with IR LED receiver
I have some dark IR led, and want to know if it is be situable to detect pure heat (not visable glow ir radiation) in well lighted desk?
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Something like termal camera, but in one spot, any simple circuit?... -
Hello everyone,
i was reballing the power manger of a moto g84, after applying heat i tried to power on and it wouldn’t.
i injected 1.5v to some capacitor that seem in short because both side beep if tested.
when i inject i feel the cpu burning;
since the cpu is exactly on the other side of the board, is that possible that the heat from the reballing damaged the cpu? do you know where i can find schematics or what can i do?
i know this is not enough to explain the situation so if you need any other info ask me please!
Thank you very much in advance11-08-2024, 02:13 PM -
Hi,
solder joints on heat sinks - how much do they matter? Could poor joints on heat sink cause issues if they are not properly joining to hot ground?
I'm looking at power source module of Panasonic plasma TV and I see many of these having visually poor quality, but could they matter? In general I would guess no, but I saw a video where someone was stressing out the importance of tightening the screws when fastening the power source board specifically for the ground to be connected properly.
Thanks
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