What Components Should be Tested on a PCB?

All electrical products will need to be tested at some point, whether it be for health and safety reasons or just general maintenance. Even the most accurately designed technology can be prone to problems and malfunctions. Printed circuit boards (PCBs) are composed of a variety of electrical components which need to function properly. In the design phase of production, PCB testing can be performed to detect and analyse areas that may be a cause for concern and help to minimise these faults. 

Here are just a few of the components which can be tested to make sure a PCB is functioning to a high standard. 

Resistors

Resistors are one of the most crucial components on a printed circuit board, they are small electronic components that produce a voltage by transmitting a current through the board. This is why it is so important to ensure they are working correctly. 

Testing can be done by isolating the resistors. This is done to ensure that they are isolated from other components within the board, after this is done a digital multimeter or analogue metre is used to measure the results. To carry out the test, the leads from the multimeter to the resistor are connected to run the test. If results are high, then it could indicate a problem within an open resistor. Other components on the board can cause the reading to be lowered if the result is too high.

Diodes

Diodes are a component on a PCB that transmits a current in a single direction, they are usually composed of a semi-conductive material between terminals. In basic terms, diodes send a current in one direction whilst blocking the current in the opposite direction. They are extremely sensitive components so caution is to be advised when testing, which is why we recommended consulting professionals like ourselves, before attempting to test your electrical equipment. 

To test a diode you are required to disconnect one end of the diode from the printed circuit board. A digital or analogue metre is used to find the black and red probes, after locating them, connect the black probe to the cathode and connect the red probe to the anode. The test is designed to either identify a leak in the diode or to check if a diode is forward biassed. 

Capacitors

Capacitors are made of an insulating material that is placed between two conductive plates, they are essential components that store energy as an electrostatic field on a PCB. Testing these components on a PCB requires one end of a capacitor to be removed from the board. Making sure the power supply matches the range of the capacitor is essential to prevent the overloading of the device. 

When applying a voltage to a PCB, there are a few things that can be tested for. One is to test to see if the capacitor has shorted, another is to check if a capacitor is leaking and also to test the metre readings to show if a jump occurs when voltage is applied to the PCB. 

How M-Tek Can Help

By choosing M-Tek for your PCB assembly and testing, you will also be doing your part to save the planet. We have achieved a net-zero carbon footprint from our use of electric vehicles, and for every circuit board we build, we plant a tree! Get in touch with one of our experts for help with your SMT and PCB assembly today. Call us on 01189 455377, or follow us on Twitter to stay up to date with our services.