Electromagnetic interference or EMI is a known term, and it means the disturbance caused by mixing of signals coming from various nearby or connected devices. However, nowadays, electronic components and devices are designed to be EMC enabled. What does this mean? This means these devices can withstand EMC to a certain extent. Electromagnetic compatibility is the ability of an electronic device or a circuit board to function normally in an EMI environment. A manufactured device is tested for EMC considering various parameters such as immunity to EMI, radiation emitted, and so on. EMC testing needs to comply with international standards such as UL listing, and ISO guidelines for EMC testing compliant labs. This post discusses EMC testing, its types or parameters, and more.
Important Pointers Regarding EMC Testing
While EMC enabled device or board can function normally, each has their own upper limit based on their design and other parameters, beyond which they become susceptible to EMI. EMI Shielding and EMC are like two sides of the same coin and both can go well together; however, even for EMC devices, especially PCBs, EMI shields play an important role. While EMC has its own benefits, such devices or boards must be tested thoroughly to check their tolerance for EMI. Here are some pointers about EMC testing.
- EMC as a factor must be considered during the design and layout stage itself; it cannot be introduced later. So, the design of a board or device must be EMC friendly.
- Component selection is also an important part of this process. This is because certain components and their materials may be susceptible to noise from the periphery, especially beyond a certain frequency.
- The focus here is on signal attenuation to prevent EMI and emission control which enhances the compatibility of the board or device.
- EMC testing is performed to check the susceptibility of the device towards EMI that radiates from other devices. Another factor of this testing is to check the signals that radiate from this board or device which may negatively impact the peripheral devices
- The first test is called susceptibility testing, wherein the test device is subjected to powerful radiation or pulse signals. The upper limit to which the device can function in this environment is checked. This test helps manufacturers define or quantify the transient immunity a device or board has. Beyond that, EMI shields would be required.
- The second test checks the emissions from the test device, and is called emissions testing. This test measures the strength of the signals or waves radiated by the device in the field. It also checks their impact on the peripheral devices, wires, and so on. This is done with the help of EMI analyzers with standard bandwidth and detectors.
Both EMC and EMI shields make a device safe from the effects of EMI, and for both EMC testing is crucial. While EMC is important for any electronic device, PCBs, and so on, using EMI shields for boards is the flip side of EMC that helps control EMI. This is because no device or PCB can withstand high amounts of EMI radiated from another device or board component, beyond the design limit. This is why shielding PCBs from EMI is just as crucial, whether you are a manufacturer of PCBs, electronic devices, or components. XGR Technologies’ SnapShot ® EMI SnapShot EMI shields offer quality shielding for frequencies from below 1 GHz to 12 GHz. The company offers customized PCB EMI shields to cater to specific requirements such as size and shape of PCBs. For further information, questions, or requirement sharing, you can contact the team via phone or email.
