Schematic help

Thread Starter


Joined Sep 6, 2022
Hello all,
I would like to receive some help with my study in Schematics. I've attached a Schematic and a few questions. Any help would greatly appreciated. Thank you in advance.


Study the following schematic of a rudimentary USB-to-Serial converter:

Consider the scenario where you are required to troubleshoot an issue with the above shown converter. The problem statement from the user is as follows:
“After I have connected the converter it does not communicate with the Device Under Test. I have confirmed the power and USB connections were correct but still it does not communicate.”
Question 1
Describe the first steps you would undertake to determine the likely cause of the problem.
Question 2
Indicate on which components would you conduct a measurement to confirm that the incoming voltage is present and correct.
Question 3
Indicate on which component would you conduct a measurement to confirm that 5V and 3.3V is present in the circuit.
Question 4
Assuming both VIN and 5V is present but 3.3V was measured at 0V, in which functional block is the problem most likely?
Question 5 (Bonus)
What type of component is Q1 and which tests can be performed with a multimeter to confirm the component is functional?



Joined Jun 30, 2021
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