This article presents design guidelines for helping users of HDMI mux-repeaters to maximise the device’s full performance through careful printed circuit board (PCB) design. We’ll explain important concepts of some main aspects of high-speed PCB design with recommendations.
This discussion will cover layer stack, differential traces, controlled impedance transmission
lines, discontinuities, routing guidelines, reference planes, vias and decoupling capacitors.
The pin-out of a HDMI mux-repeater is tailored for the design in HDTV receiver circuits (see Picture below). Each side of the package provides a HDMI port, featuring four differential TMDS signal pairs, thus resulting in three input and one output port. The remaining signals comprise the supply rails, Vcc and ground, and lower speed signals such as the I2C interface, Hotplug-detect and the mux-selector pins.