Definition

Termination provides impedance matching at the end of a transmission line to absorb signal energy and prevent reflections. Series termination places a resistor at the source, matching driver output impedance to the line. Parallel termination places a resistor at the receiver equal to line impedance. AC termination uses capacitor in series with resistor to reduce DC power. On PCBs, termination resistors are typically discrete SMD components (0402 or 0603). For tight tolerances, specify 1% resistors. Embedded resistors in the PCB stackup offer shorter interconnects and save board space for high-speed applications.