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-1

Instead of two resistors, use a resistor and a Zener diode. Make sure the resistor is low enough to ensure the supply voltage to the 245 won't drop below 2.8V when it takes its maximum load and leave the Zener to do the regulation.


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You need to make sure the current to the IC is much smaller than the current through the voltage divider (preferably at least an order of magnitude, better two, but chips use very small current, so should be doable if temporary). As as temporary solution - maybe. Try it with potentiometer, you may want to adjust it a little bit. The chip will pull the ...


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I'm going to assume you have a common reference voltage (a.k.a. ground/GND), which is pretty much a given for PCIe. As a general rule, small differences in supply voltage will have little effect. For example you could have everything powered off a single supply, but voltage drop across a board may result in one device running of a marginally lower voltage. ...


-1

As long as the signal voltage is the correct voltage that the receiving device expects, and the ground is connected, it doesn't matter how you got that voltage.


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Turns out the issue was a dead power mosfet. Replaced the part and the circuit worked fine. I also replaced the 2n7000 with a lower threshold mosfet to make sure it actually switches.


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There is nothing inherently wrong with the circuit. It will switch very slowly (which could be hard on the output MOSFET) because of the 100K, but that also limits the current into your MCU output. Probably your implementation is at fault. Check the pinout on the 2N7000 and the other MOSFET and the resistor values, or take a sharp photo of your circuit and ...


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What might be happening is that, during turn-off, voltage drop across 2n7000 might be bigger due to 3.3V dc source being near to 2n7000 threshold voltage(check in datasheet) when it is applied across VGS. Edit: Explanantion: During turn-off, the charged Q1 gate capacitor has to be discharged and the path following is through the Q2 and logic controller ...


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There are bidirectional level shifters designed for I2C, that have internal speed-up logic to improve the risetime. These can certainly do a couple of MHz no problem. Maxim appnote: https://www.maximintegrated.com/en/design/technical-documents/app-notes/1/1159.html There is also the pass-transistor type, but you need to add strong-enough pull-ups to get the ...


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