A 3-D Finite Difference Method for Obtaining the Steady-State Temperature Field of a PCB Circuit

The temperature rise caused by the heat generated by the on-board LED driver module during work will lead to the rise of product failure rate. The thermal analysis of this drive module should not only consider the heat and packaging of the LED itself, but also the influence of other power components. Common commercial thermal simulation software, such as ANSYS ICEPAK or FLOTHEM, usually requires detailed thermal models for such printed circuit board (PCB)-level thermal simulation, and requires a large number of simulation parameter settings and a long simulation time to obtain temperature results that are barely close to the actual. In this article, a 3-D finite difference method is proposed to obtain the steady-state temperature field of PCB circuit. The model can be used to calculate the steady-state temperature field of PCB circuit by setting different component sizes, power, and thermal conductivity. This article uses this method to calculate the temperature field of PCB steady-state working with MATLAB. The experimental measurement of PCB is compared with thermal simulation by ANSYS ICEPAK. It proves that the temperature results obtained by this method are similar to the actual test temperature compared with ANSYS ICEPAK. The time required for calculation is greatly reduced.