If we design for a 3A maximum load and try to limit the temperature rise of the PCB to 10°C, we calculate that a 50mil width can accommodate close to 3.5A for this 4-layer stackup. A 50mil switch node width is a good target for this design, since it provides some margin above the 3A maximum load.
Enabling scientific research by hosting the Cherry Creek Supercomputer for the University of Nevada, Las Vegas.
Connecting Nevada’s rural schools to the Internet by extending fiber connectivity from the Switch SUPERLOOP®.
Lending executive-level leadership on technology, education and arts through state-wide board Memberships.
Spearheading the growth of the technology industry in Michigan, by building the largest data center campus in the eastern United States.
Different tradeoffs can be made based on the allowable temperature rise of the PCB. While it is common to see the trace sized to be as wide as the inductor pad, we can see from this case that a narrower trace is fully capable of meeting current and thermal requirements.
A switch node trace consists of a PCB trace above a reference plane, and can be viewed as a significantly shortened version of a microstrip line, particularly at high frequencies. A microstrip line with controllable impedance is used in high-speed transmission line applications for digital, high-speed analog, and radio frequency (RF) signals.
Even though the applications for a switch node and microstrip transmission line are different for the intended signals they conduct, their geometries exhibit similar properties for time-varying electric and magnetic fields.
