Ibis Model Output Impedance Correction Approach Using CCCS

Abstract

With the CMOS technology size scaling aggressively and the transmitter (TX) outp¬u¬t resistance becoming smaller and smaller, it becomes necessary to have a good impedance correlation between TX and receiver (RX). The mismatch between the impedances can cause a noise and a response which will dramatically decrease the efficiency of the circuit. Nowadays, those mismatches are being tested using IBIS (Input/output Buffer Information Specification) models owing to low cost and testing speed. A method is proposed to use a current-controlled current source (CCCS) which will decrease the mismatch and make it less than 1%. The proposed method can be implemented for all types of TX drivers and IBIS models.