By Steve Hopwood, Knowles Precision Devices
With our new expanded range of enhanced safety-certified multilayer ceramic capacitors (MLCCs), Knowles Precision Devices now offers a unique combination of capability and safety certification for electronic device applications. These new surface-mount MLCCs comply with international UL60384-14 and EN60384-14 specifications and can be used instead of leaded film capacitors in AC-DC power supplies where a lightning strike or other voltage transients represent a threat to the electronic equipment.
In general, there are two classes of capacitors, Class-X and Class-Y, that are both used to minimize electromagnetic interference (EMI) and radio frequency interference (RFI) in different applications. Class-X capacitors offer line-to-line protection, which means if there is a failure, a short may occur but there is no risk of shock. Class-Y capacitors offer line-to-ground protection, which generally means that if a failure with the ground occurs, there is a risk for shock. However, since Class-Y safety capacitors have met rigorous specifications, the risk of a component failure that may result in a fatal electric shock hazard is minimized. We have designed both Class-X and Class-Y MLCCs, and the general electrical details of our new safety-certified product line is summarized in Table 1 below.