Perform an Electrical Test on Custom PCBs
When a printed circuit board (PCB) is assembled and fabricated, electrical testing is a vital process that verifies the integrity of each of its components and connections. Without this essential step, a PCB may fail to function properly and could compromise the performance of the finished product. Custom PCBs are used in numerous industries, including consumer electronics, telecommunications, automotive, aerospace, medical, and industrial sectors. Examples include custom pcb fabrication for IoT devices, wearable technology, robotics, drones, and specialized medical instruments.
Electrical testing is an integral part of the manufacturing process, and it’s especially crucial for multi-layered boards and densely populated boards with high-value components. This test ensures that all electrical circuits are correctly established and free from issues like shorts, opens, or incorrect component placements. It’s also a great way to test for ionic contamination and other factors that could affect the quality of a board.
The first step to electrical testing a PCB is to power it up and observe the voltages at the input and output of the board. If a voltage is missing at the output, it typically indicates that the voltage regulator or another component along that line is damaged and draining massive amounts of current. Look for signs of overheated components, such as an acrid scent or hot spots on the surface of the board, and remove the offending component to verify that the voltage is back to its expected value.
How to Perform an Electrical Test on Custom PCBs
After removing the overheated component, power up the circuit board again and examine the voltages at the input and output of each layer to make sure that all are in place. If a layer’s voltage is significantly different from the others, it might indicate an error in the design or manufacturing of the circuit board. Examine the schematic to identify the faulty layer and use a multimeter to check for the correct values for the voltages.
Another electrical test to perform on a custom PCB is called the Rogowski coil test. This test uses a transmission line to send a pulsed signal across the circuit board. If there’s an impedance mismatch on the circuit board, a portion of the pulse will reflect off the transmission line and be detected by a TDR (transmission line diagnostics receiver). The resulting waveform provides information about the location and nature of the problem.
The key to ensuring consistent, accurate results during your electrical testing is using the right software for your specific needs. Using the right ECAD data and sourcing from trusted suppliers will help you streamline your design process and reduce the time it takes to deliver an error-free circuit board. Ultra Librarian offers an extensive library of accurate electrical data and ECAD models that are compatible with the fixtures used in PCB electrical testing, allowing you to save time and effort while increasing accuracy. Try it out for free today!
