Analysis And Design Of Signal Integrity Of HDMI In Set Top Box

The high integration degree of modern digital chips,high circuit wiring density and high data transmission rate make high-speed digital signal more and more vulnerable to be interfered so that the signal integrity of digital signal was greatly reduced.The integration of set-top box hardware board is high,its HDMI transmits digital signal rate is also high,so it is easy to be interfered.At present,hardware engineers mostly rely on their working experience to design signal integrity of HDMI in set-top box.It often appeared with the crosstalk problems which had resulted in poor quality of HDMI digital signal transmission and even unstable transmission problems.Therefore,it is of great technical significance and application value to analyze the reasons for the formation of crosstalk of HDMI in set-top box and design effective interference suppression for the design and development of HDMI in set-top box.Based on a digital set-top box development project of a company,this paper analyzes and improves the signal integrity of HDMI of set-top box.This paper first introduced structure and main signals of HDMI in set-top box and then analyzed the reasons for the deterioration signal integrity of HDMI in set-top box so as to provide support for HDMI modeling and simulation.Furthermore,this paper made a specific analyse of the possible interference sources of HDMI in the set-top box are analyzed in detail,and set up a model for the main signals of HDMI,including layout and wiring,PCB laminates,interference sources and HDMI signal transmission location in the single board of the set-top box and other models.Based on the analysis of the causes problems of HDMI during the use of set-top box,crosstalk design was improved.This paper used Hyperlynx to establish the minimum differential signal model of HDMI in set-top box,simulate the HDMI design parameters and crosstalk and then summarized the design rules and improved the PCB design for HDMI in set-top box.Finally,we made a measurement for the signal improvement scheme of HDMI in set-top box,including power quality,eye quality and radiation test with the results that the improved design was effective to improve the signal integrity ofHDMI in set-top box.