Recent content by newengr

Thanks for the analysis. After looking at that more, one thing pops out to me. One of the assumptions here is that there is a uniform current. By making that assumption, current density J can be simplified to current I. At higher frequency, the skin effect can cause a significantly higher...

If the current density decreases, doesn't H also decrease?

The differential form is a function of current density though.

Hi Berkeman, Thanks for your response. I'm somewhat familiar with Ampere's law, but the equation shown is simplified. Going to Maxwell's equations, it appears that the curl of H is related to current density. So I was thinking that reducing current density could also be an effective way to...

If I want to carry 10 A through an 8 AWG wire, I understand that there will be a specific magnetic field around the wire which will decrease as I move outward from the wire radially. Let's consider the center of that wire as coordinates (x,y)=(0,0). An object located at (0,10) would see a...

would it be represented as a nonlinear resistance? Or like several series resistances where the resistance increases as you move away from the electrode?

I found this discussion which is pretty much exactly what I'm looking for, but I still just do not understand where it is going. The plasma ball thing is a perfect example. Electrons are moving from the electrode in the center to where...

In a normal circuit it's easy enough to visualize the path electrons take through a wire. Even considering leakage current in a capacitor, it's easy enough to visualize a large parallel resistance that current "leaks" through. Is there such a way to visualize corona discharge? I get that it...

The package I'm interested in is TO-263-8. I was trying to look for app notes or anything on this device to determine what voltage I need to start worrying about potting. It's a 3.3 kV device. I may actually see voltages as high as 2.2 kV. What are your thoughts on this one? The pads are back...

The source of the EMI is a MOSFET switching on a DC bus. The target are nearby circuits referenced to a the midpoint of the bus or the -DC rail; both cases work. I extracted the parasitics which include capacitive coupling and inductive coupling terms using Q3D. I have the netlists for...

I am new to EMI modeling and just looking into it. I would like to create a circuit schematic to represent the inductive and capacitive coupling paths in one schematic. All that I've been able to find online is references discussing each independently. Is this the best approach if you want to...

Ah I like the idea about frying it. It's at least worth a shot. Even cutting the device with a saw may work, gap would need to be large enough so that I don't see corona there which may be hard. It's still worth a shot though. I'm hoping for the high current to fry it though because that would...

Yes, that's correct; the problem is the device conduction. The diode within the MOSFET is actually the problem because I'm using AC. During the positive half cycle of the excitation, Vds is positive. The MOSFET is blocking and the body diode of the device (basically an antiparallel diode) is...

I'm not wanting to HiPot test the device. I'm wanting to HiPot with my board with the device installed. If I wanted to test the device, I would use a curve tracer. I understand that HiPot is for insulation testing. The insulation performance of the board will be different than the insulation...

This is just for experimental purposes, nothing production. I'm not wanting to test the device insulation but the board and footprint. If it was device then I would definitely use a curve tracer. I know there are IPC standards for minimum creepage/clearance or I can encapsulate the device if I'm...