Far-end crosstalk reduction in PCB interconnects using stepped impedance elements and open-circuited stubs

Abstract

In this work, new trace configurations using stepped impedance elements and open-circuited stubs to reduce far-end crosstalk in printed circuit board (PCB) interconnects are introduced. The goal of this study is to reduce crosstalk without using additional PCB components in the design. Specifically, we use stepped impedance elements and opencircuited stubs of uniform length and width on the victim traces to suppress high-frequency electromagnetic interference and to equalize propagation delays or capacitive and inductive couplings between PCB traces. The overall design is very similar to the usual low-pass filter configurations, which are difficult to implement in the prototype testing. The proposed approach shows remarkably better results when compared with conventional intervening guard trace schemes.

Non-uniform PCB traces with prescribed frequency bands for improved crosstalk immunity

“…It is worth mentioning that the sharper the cutoff of the LPF, the better the far-end crosstalk at the cutoff frequency. [5] This allows controlling the location of the steepest reduction in the crosstalk response. The synthesis of a non-uniform trace [8,9] starts by subdividing the line length (d) into K electrically commensurate short sections with a length of Δz as given below:…”

“…For this reason, one may employ a lowpass filter (LPF) configuration on the victim traces either with stepped impedance elements or with open-circuited stubs. [5] This method achieves better performance than designs using guard traces alone; however, a drawback on stepped impedance designs is their low capability in handling high current densities due to the narrow trace width of the high impedance sections. Moreover, the open-circuited stubs design suffers from high radiated emissions.…”

“…Moreover, the open-circuited stubs design suffers from high radiated emissions. [5] In our proposed trace depicted in Figure 1, such limitations do not exist as a non-uniform trace of a continuously varying impedance Z(z) with tolerable corresponding width W(z), and propagation constant β(z) is employed.…”

Design and Realization of an Aviation Computer Micro System Based on SiP

“…Reflection means that when a signal propagates on a transmission line, a part of the signal is transmitted forward due to a discontinuous portion of the impedance, and another part of the signal returns along the original path [18]. Crosstalk refers to undesired voltage noise interference caused by electromagnetic coupling to adjacent transmission lines when signals are transmitted on the transmission line [19]. One of the most important issues with signal integrity is the reduction in signal crosstalk and reflection [20].…”

Crosstalk Cancellation Method Based on Unitary Transformation of Coupled Transmission Lines-Channel Transmission Matrix

“…Currently, crosstalk is suppressed mainly from the physical structure of circuit board and transmission line [5][6][7][8][9][10][11], but the effect of these methods is limited. In mobile communication systems, MIMO (multi-input and multi-output), which employs multiple antennas at the transmitter to transmit signals independently and receives the signal with multiple antennas to recover it, is used to describe an abstract mathematical model of multi-antenna wireless communication system.…”