Do I need to disconnect the processor when testing the diodes on the board?

Question

Do it yourself

Hello!
I measured the voltage on the board, turned on the test stand.
I want to check usb with a diode dialing multimeter.
Question: since the stand is still assembled, is it necessary to disconnect the processor in order to check the USB port pins?

Answer 1

Not necessary. There are many reasons, here are the first two that came across:
1. According to the scheme, the processor is very far from the USB ports, there is no direct connection, so the voltage on the probes of your multimeter simply will not reach it.
2. The signal lines of the processor are the gates of field-effect transistors, their breakdown voltage is about 20 volts, i.e. much higher than that which the multimeter gives out on the probes. And with the supply lines of the processor it is even more interesting. A modern percent is powered by voltages of the order of 1 volt, but with terrible currents, on the order of several tens of amperes. So the meager current that is created on the probes, the percent will not even notice. And vice versa - for a multimeter, the power lines of the processor will be like a short circuit. Those. the multimeter is safe for the processor even when connected directly.