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Difficulty finding suitable parts for a power MOSFET and its gate driver

I'm looking for a series of parts (Current-Sense Amplifier, Voltage Level Shifter, Power MOSFET), but I'm looking for them in a specific format.  I'm looking to use the amplifier and the voltage level shifter in conjunction with each other to act as the gate driver for a power mosfet, but the reason I'm emailing is because I'm having difficulty finding them at the specs I need. What I'm looking for is for all three to fit each other in terms of I/O of course, but with the following:
-The Current-Sense Amplifier needs to be able to receive input at about 10V and from 5mA or greater.  It can have either one or two output channels
-The Voltage Level Shifter needs to be able to deal with the output from the amplifier, and shift the voltage up from about 10V to a minimum of 100V, preferably going to at least 110V.
-From here, the Power MOSFEt needs to be able to accept the output of the shifter into its gate, using the received voltage and current to help drive the gate switch on the mosfet.  I'm also looking for it to be able to accept about 170V on the source side.  On that note, I'm looking for an nMOS, but a pMOS could suffice if it still works.
It's a bit, but I've been unable to find what I'm looking for so far.  I would be incredibly grateful for any help I can get, even if it's only one of the parts I need.
I'm looking for a series of parts (Current-Sense Amplifier, Voltage Level Shifter, Power MOSFET), but I'm looking for them in a specific format.  I'm looking to use the amplifier and the voltage level shifter in conjunction with each other to act as the gate driver for a power mosfet, and so far I've been unable to find anything that fits the bill.  What I'm looking for is for all three to fit each other in terms of I/O of course, but with the following:
-The Current-Sense Amplifier needs to be able to receive input at about 10V and from 5mA or greater.  It can have either one or two output channels
-The Voltage Level Shifter needs to be able to deal with the output from the amplifier, and shift the voltage up from about 10V to a minimum of 100V, preferably going to at least 110V.
-From here, the Power MOSFET needs to be able to accept the output of the shifter into its gate, using the received voltage and current to help drive the gate switch on the mosfet.  I'm also looking for it to be able to accept about 170V on the source side.  On that note, I'm looking for an nMOS, but a pMOS could suffice if it still works.
It's a bit, but I've been unable to find what I'm looking for so far.  I would be incredibly grateful for any help I can get, even if it's only one of the parts I need.

  • Keith,
    Not sure why this post was moved here aside from the MOSFET portion of your question. I can try to help with at least that part.

    You say the source may have to handle up to -170V so my question would be what would the drain voltage be under those conditions. Or more precisely, what is the worst case drain to source voltage (and source to drain voltage) for that matter?
  • Under those conditions, I'm looking at the drain voltage to be low, about 3 or 4 volts (I'm looking at a potential source-to-drain voltage of around 166V DC).  Worst case I'm not certain however, though it will likely not be too much lower I'd imagine.

  • Keith,
    Because of the inherent body diode, no N-Channel FET will be able to handle a source to drain voltage of 166. You will need to put in an external resistor that severely limits the amount of current the body diode will see, and limits the maximum source to drain voltage across the FET.

    Then the question becomes, what is the worst case scenario Vds the FET will see or needs to be capable of blocking?