Effect of material properties on PCB frequencies in electronic control unit

Abstract

With advancement in Artificial intelligence, Internet of things and next generation of mobility going towards autonomous driving, the electronic control units used for power steering need to be redundant, highly reliable and intelligent. The above challenge forces design engineers to smartly enhance the electronic components with use of multiple PCB stacked one above another. PCB is one of the main parts of the control unit on whichSMD components are populated. Therefore, comprehensive knowledge of PCB dynamic behavior is important for fatigue evaluation of SMD and other electronic components.This paper discusses the mechanical dynamic responses of PCBs using different material properties, e.g. isotropic, orthotropic and PCB homogenizing properties. Simulations are carried out in Ansys to predict the PCB frequencies and mode shapes. In order to validate the simulation results, measurements are also performed to predict PCB frequencies, mode shapes and frequency response funsctions. Measurements are carried out with PSV-400 scanning laser vibrometer from Polytech and post processing of measurement data is done with help of Polytech for visualization of mode shapes.