SUMMARYThe data rate of VLSI interconnections has been increasing according to the demand for high-speed operation of semiconductors such as CPUs. To realize high performance VLSI systems, high-speed data communication has become an important factor. However, at high-speed data rates, it is difficult to achieve accurate communication without bit errors because of inter-symbol interference (ISI). This paper presents highspeed data communication techniques for VLSI systems using TomlinsonHarashima Precoding (THP). Since THP can eliminate the ISI with limiting average and peak power of transmitter signaling, THP is suitable for implementing advanced low-voltage VLSI systems. In this paper, 4-PAM (Pulse amplitude modulation) with THP has been employed to achieve high-speed data communication in VLSI systems. Simulation results show that THP can remove the ISI without increasing peak and average power of a transmitter. Moreover, simulation results clarify that multiple-valued data communication is very effective to reduce implementation costs for realizing high-speed serial links. key words: high-speed interface, Tomlinson-Harashima precoding (THP), intersymbol interference, multiple-valued signaling, low-voltage VLSI systems

As the Required Data Rate for VLSI System Communication Increases, Channel Bandwidthlimitation Becomes a Crucial Problem as High-Frequency Channel Loss Degrades the Transmission Performance.In this Paper, we Compare Non-Return-to-Zero (NRZ) Binary and 4-PAM (pulse Amplitudemodulation) Coding Techniques for High-Speed Data Transmission by Fabricating a Test Board of a Microstripline. by Extracting the Micro-Strip Line Parameters, we Carry out Co-Simulations to Evaluate Spectrallyefficient Coding for High-Speed Data Transmission.We Consider the Conditions for which 4-Pamsignaling Provides an Advantage over NRZ Signaling from the Viewpoint of Channel Profiles.

The performance of advanced VLSI systems is limited by the interconnection bandwidthinside/between chips rather than individual performance of transistors. The attenuation or deteriorationof signals, arises from physical phenomena in transmission lines, restricts the maximum frequencyat which the signal can transmit. This paper investigates coding techniques that can modifysignal spectrum suited to channel frequency response based on the concept of spectrum shaping ofsignals. We discuss three types of coding techniques for high-speed serial links to evaluate their performanceas well as the feasibility for realizing efficient data transmission.