casemod
Member level 1
Hi guys,
I have a question. I dont normally see IGBT's or mosfets being used in linear power supplies. Many of the components on these are only rated for their output load when TJ = 25C and the transistor quickly burns under short circuit conditions.
For a 0-30V 5A (or 0-60V 2.5A) power supply to be fool proof, even if permanently short circuited, I would need about 24*1.41*5A = 170W of power dissipation, lets say a worst case scenario of 200W with a TJ = 125C and a heatsink = 60C.
Its not too hard to find mosfets or IGBT's with such specs, so my question is can these be used in place of the bipolar with suitable modifications to the driving circuit? If not what are the reasons?
I have a question. I dont normally see IGBT's or mosfets being used in linear power supplies. Many of the components on these are only rated for their output load when TJ = 25C and the transistor quickly burns under short circuit conditions.
For a 0-30V 5A (or 0-60V 2.5A) power supply to be fool proof, even if permanently short circuited, I would need about 24*1.41*5A = 170W of power dissipation, lets say a worst case scenario of 200W with a TJ = 125C and a heatsink = 60C.
Its not too hard to find mosfets or IGBT's with such specs, so my question is can these be used in place of the bipolar with suitable modifications to the driving circuit? If not what are the reasons?
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