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Power & Energy

3 Posts authored by: jc2048
  Previous blogs:   Experimenting with MOSFETS: Total Gate Charge Experimenting with MOSFETs: Transfer Characteristic   Introduction   More experimenting with MOSFETs. In the last blog I looked at the transfer characteristics but it wasn't very easy to see from the graph I plotted where the threshold was. The threshold is measured at a drain current of 250uA and that is down in the noise for the current probe I was using. So this is a different approach to finding the ...
This is a short follow-up to Experimenting with MOSFETS: Total Gate Charge where I looked at 'total gate charge' for an IRF730, an n-channel power MOSFET.   Since I still had the test board wired up, I thought it might be interesting to see if could get a quick plot of the transfer characteristic - the way that the drain current varies with gate voltage.   I've taken the previous circuit, bypassed the constant current generator in the drain and then plotted the drain current against ...
Introduction   More experimenting, this time with MOSFETs.   If you've ever designed with a MOSFET, I'm sure you've seen the kind of curves that are usually present in the datasheet showing the relationship between the total gate charge and the gate voltage. Here's one such graph from a datasheet for a Vishay IRF730 device:   They always have the same sort of shape to the curve, though the position of the plateau, halfway up, varies in both voltage and the amount of charge to ...