High-speed signal link design adopting parallel capacitors

Abstract

The invention provides a high-speed signal link design adopting parallel capacitors. The link design comprises a parallel capacitor, a parallel capacitor transmission line and a signal backflow layer.The parallel capacitor transmission line is arranged below the parallel capacitor, the parallel capacitor is welded to the parallel capacitor transmission line through a capacitor bonding pad, the backflow layer is arranged below the parallel capacitor transmission line, and the parallel capacitor transmission line comprises a width gradual change part, the width of the transmission line of the part is linearly narrowed from a position which is a certain distance away from the parallel capacitor bonding pad, in addition, the signal backflow layer right below the parallel capacitor is integrally dug out. According to the high-speed signal link design adopting the parallel capacitors, impedance mismatch and signal loss on a transmission line can be avoided.

Description

technical field [0001] The invention relates to the field of radio frequency technology, in particular to a high-speed signal link design using parallel capacitors. Background technique [0002] Driven by the current demand for 5G wireless fronthaul and ultra-large broadband data centers in the fifth-generation communication network, the transmission rate requirements for its core components are getting higher and higher. High frequency, high speed, and high density have gradually become a significant development trend of advanced communication products. one. High-frequency signal transmission and high-speed digitalization force PCBs to move towards micro-holes and buried / blind holes, finer wires, and uniform thinner dielectric layers. High-speed PCB design technology has become an important research field. In high-speed digital circuit systems, if the impedance mismatch of the transmission line will cause data signal reflection, resulting in signal distortion such as overs...

AI Technical Summary

Problems solved by technology

[0003] Under the requirements of ensuring the impedance matching of the PCB12 transmission line, it is often necessary to add design schemes such as series capacitance 11 on the PCB circuit according to the design scheme of the actual circuit and chip, such as figure 1 , in order to realize the effect of cutting off the DC signal and passing the AC signal, similar to a high-pass filter, the size of this capacitor 11 is 0201, 0402 or 0603, etc., and the size of the capacitor is quite different from that of the transmission line 13, and it will be felt when the high-frequency electromagnetic field is transmitted Obvious abrupt change in impedance, resulting in degraded high-speed performance of the signal

In terms of high-speed circuit design, in order to achieve lower-loss signal transmission and the passage of wider frequency signals, it is often necessary to design two capacitors with different capacitances in parallel on the transmission line, but since two capacitors are connected in parallel on the high-speed transmission line It will cause stronger impedance mismatch and signal loss, so this high-speed capacitor parallel design is currently difficult to achieve

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