Problems due to impedance mismatch

When source, line and load impedances are not equal, the problems are:

1. Signal reflections from the load/discontinuity back toward the source (Γ = (Z_L - Z₀)/(Z_L + Z₀)).
2. Ringing, overshoot and undershoot on edges; can exceed the device ratings or cause false triggering.
3. Signal distortion and degraded signal integrity, with false logic levels and data errors.
4. Increased delay and timing errors (settling time), and reduced maximum speed.
5. Loss of power transfer to the load (reduced amplitude).
6. Higher EMI/crosstalk radiation from the reflected energy.