Second one seems like misbehaving right? Should I remove it for testing outside board?
Help reading schematic voltages input/output
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PQ3502 out. Behaves like it's meant to. SD 0.5V / DS blocked. I didn't know it could behave shorted in diode mode just because of the low core rail impedance? Or it shouldn't show shorted behavior even like that?
Measuring PQ3502 pads alone in resistance mode gives this: DRAIN- 58Ω SOURCE- 0Ω and GATE- 5.3MΩ. Mosfet still off board.Comment
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Resistance to GND on any rail is a relative concept and not absolute concept. You cant put a fixed number as it varies from platform to platform. Resistance to GND on cpu core at 0.9ohms on vcore is fine for a 9th gen gaming board but may be considered short for a 6th gen cpu. Similarly GPu coil resistance to GND on a gaming laptop may be fine at even 0.1ohms but its definitely shorted for a normal notebook motherboard. Have seen 100 ohms resistance to gnd on ram coil as well as more then 500oms on the same rail in other board. So in a nutshell, there is no yardstick to conclude what can be considered shorted and it will vary from platform to platform. Only experience will help you in right conclusion.
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Low-side MOSFET is in parallel with CPU, so it measures the same as expected.OpenBoardView — https://github.com/OpenBoardView/OpenBoardViewComment
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mcplslg123 Oh my, I thought I could've made my journey easier but it seems like I have to fight every board to learn. Thanks for insight.
piernov Thanks again. I think I'm running out of options. Getting closer to swapping the IC. Any suggestions to not burn such complex IC while hot air-soldering a replacement?Comment
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by EasyGoing1I have a 40 volt AC transformer that I put a bridge rectifier on, and I wanted to see the input signal and the output signal on the same screen on my scope, so I set one channel up with the test lead on one side of the input and the ground lead on the other side of the input, then I used another channel on the scope and clipped the test lead on the positive side of the output then the ground on the negative side of the output.
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09-12-2024, 03:04 PM -
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by dennis_elx33Hello All,
i would like to post an interesting topic regarding 3-phase stepdown transformer which we suspect to cause an overcurrent (138A) which resulted to power tripped off of the HV power supply (80KV output).
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