On-die termination

On-die termination (ODT) is the technology where the termination resistor for impedance matching in transmission lines is located inside a semiconductor chip instead of on a printed circuit board.

Overview of electronic signal termination

In lower frequency (slow edge rate) applications, interconnection lines can be modelled as "lumped" circuits. In this case there is no need to consider the concept of "termination". Under the low frequency condition, every point in an interconnect wire can be assumed to have the same voltage as every other point for any instance in time.

However, if the propagation delay in a wire, PCB trace, cable, or connector is greater than 1/6 of the rise time of the digital signal, the "lumped" circuit model is no longer valid and the interconnect has to be analyzed as a transmission line. In a transmission line, the signal interconnect path is modeled as a circuit containing distributed inductance, capacitance and resistance throughout its length.