FeedThru multilayer varistors (MLVs) were developed to decrease the parallel inductance of a standard discrete MLV, maximize series inductance, and tune capacitance. The FeedThru devices can be packaged into a single-element 0508 or a four-element 0612 FeedThru form factor.
Regardless of the specific configuration, all FeedThru MLVs exhibit significantly faster turn-on times (on the order of <250ps) and relatively high Q S21 curves. When comparing the S21 curve of standard MLVs to that of the FeedThru MLV, engineers can see the specific applications where each part type excels. Discrete MLVs are ideal for broadband EMI attenuation, as well as transient suppression.
FeedThru MLVs can be used for specific frequency attenuation (more like a notch filter), as well as transient suppression. The FeedThru varistor equivalent model, schematic, and S21 curves are shown here. The S21 curve sets are plotted for both low-capacitance (0.1J) and high-capacitance (0.3J) devices. These curves illustrate that FeedThru MLVs can be used in applications such as radio frequency-linked equipment, monitors, sensors, system power supplies, and communication busses.
In addition to their significant electrical advantages, FeedThru MLVs save more than 90% of the board space that equivalent diode solutions, ferrite beads, and capacitors would utilize. Further, FeedThru MLV reliability is better than that of Zener diodes.