HDMI Layout Guide: Managing 100 ohm Impedance and ESD Protection

To preserve signal quality over HDMI using high-speed differential pairs, a 100Ω differential impedance is required. HDMI's differential pairs require tighter coupling, constant spacing, and a continuous reference plane to maintain signal integrity. Signal traces should be as short as possible with no stubs, and all trace lengths should be matched within their tolerances. The HDMI connector should be placed at the board's edge, only using direct routing of differential pairs to minimize signal loss. Low-capacitance ESD protection devices should be added to HDMI connectors as close as possible to protect the circuit from voltage surges generated by ESD before they reach sensitive integrated circuits. A poor connection here will decrease video performance and could lead to ESD-induced signal failure.