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MOSFET with Low Vgs(th)?

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Loq

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low vgs mosfet

I am looking for small P MOSFET with low Vgs(th) to work inder 3.3V. Thanks
 

lastdance

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mosfet vgs

check out vishay's website
www.vishay.com
It's a relatively new kind of sub-logic FET.
 

    Loq

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Vamsi Mocherla

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vgs(th)

Did you mean, Low Vth devices? If that is the case, your foundry should have a low Vth device.
 

    Loq

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Loq

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vgs mosfet

I have to work with discrete components so I will see with vishay products.
Do you know a simple scheme to drive them not too slowly?
Thanks
 

lastdance

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fet vgs

it depends on your drive current. what do u have currently?

But, u can use a mosfet driver if u want really fast respose.
otherwise, u can build a simple buffer using discrete components.
 

    Loq

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Loq

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low vgs fet

the driver solution could be simpler. But do you know a part working under 3.3V. It seems there are all specified for 5V operations.
The current I have to drive is about 100mA. I want to shunt a laser diode.
 

lastdance

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mosfet low vgs

LTC1693 is a simple chip that i have used before, however, the supply voltage was 5V. The spec. is somewhere around 4.5V for minimum. I think if the UVLO is below 3.3V, u can still use it, with lower drive. Have to check the datasheet for Linear Technology's website. The only reason for having UVLO is because too low a voltage may not fully enhance the FET, as the thresholds were high. However, with the new generation of low threshold FETs, new drivers should comfortably enhance it with 3V and above.
Sorry for not being able to give u a part no..
 

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pokemon

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low vgs

you can check out Martin's web site
 

    Loq

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Loq

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vgs fet

Thank you pokeman.
Can you gibe me the martin's web site adress because I can't find it.
 

niks

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very low vgs mosfet

try BSS138
 

    Loq

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