Research on the Influence of Solder Mask on Signal Integrity in High Speed PCB

With the development of electronic technology, circuit systems are becoming more and more high-density and high-speed, and the influence of solder mask (S/M) on signal integrity is becoming more and more important. Aiming at the design requirements of stable impedance, low reflection and high transmission of signal in the Printed Circuit Board (PCB). This paper establishes the circuit model and electric field model of the transmission line to analyze the influence of different solder mask type and thickness on its effective dielectric constant, and then use simulation software to establish three-dimensional models of the transmission line, PCB structure and solder mask, and further study the influence of solder mask change on the effective dielectric constant, characteristic impedance, return loss and insertion loss of the transmission line, so as to study and analyze the influence of the solder mask on the signal integrity of the transmission line. Finally, on the basis of these studies, this paper proposes an optimization strategy to provide a reference for the design of high-speed PCB.