Pre-Clock/Data Recovery Multiplexing of Input Signals in a HDMI Video Receiver

摘要

High Definition Multimedia Interface (HDMI) receivers use digital multiplexer at the input stage after equalization, clock and data recovery for each channel of each port. Described herein is the use of an analog multiplexer for HDMI receiver. The purpose of the analog multiplexer is to reduce the die size and power consumption by selecting the input signal from one port out of a set of input ports, right after the equalization and hence use only one block of clock and data recovery (CDR) circuits for the receiver. This sharing of one block of CDR circuits between all input ports requires the use of analog multiplexer circuits, as the signals presented to the analog multiplexer after equalization are of low signal strength and have insufficient signal-to-noise ratio to allow handling by digital multiplexer circuitry.