A printed circuit board, or PCB, is present in almost all electronic devices. Computers, smartphones, and television sets all have them. PCBs are usually very reliable but may deteriorate because of age and misuse. If your PCB is not working as expected, take the following steps to troubleshoot the issue.
The Tools You Will Need
You would need a few simple tools to test a PCB:
- A multimeter
- Soldering iron
- Desoldering station
- Magnifying glass
Now, let us discuss how we can go about testing a circuit.
Visual Inspection
We should begin with a visual inspection of the PCB. First, switch off the power to the circuit. Look for scratches, broken traces, misplaced solder, and burn spots. See if there are any cracked chips or blown capacitors. Do a sniff test – burned components will give off an acrid smell.
Power Check
Next, turn your attention to the power module. Switch on the power. Measure the input and output voltages of the voltage regulator with the multimeter. Verify that the values are as expected. A very low voltage at the output could mean that the regulator or another point has a short circuit. See if any component has heated up (but be very careful – some parts can get quite hot). Don’t keep the power on for long if you suspect a problem.
Schematic Check
Check each connection physically and compare it with the schematic. If there are mismatches with the schematic, then the circuit is bad.
Software Diagnostics
The PCB might come with a software diagnostic package. If so, run the diagnostic program to get a report on whether the PCB is functional or damaged. The program may also identify the faulty part.
Next Steps
We have discussed some simple techniques for checking if a PCB is defective. There are more complex and expensive methods like In-Circuit Test (ICT), Flying Probe Test, Functional Circuit Test, and Boundary Scan Testing.
If you need an old PCB repaired or a new one designed and built, consider hiring BESTProto. They are a professional group of technicians and engineers who are experts in PCB assembly and PCB repair services.