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Design >> Analog Design >> MOSFET resistor
https://designers-guide.org/forum/YaBB.pl?num=1258730743

Message started by Shlapenka on Nov 20^th, 2009, 7:25am

Title: MOSFET resistor
Post by Shlapenka on Nov 20^th, 2009, 7:25am

Greetings,

what makes a MOSFET transistor act as a resistor? Is it W>L (W lenght more than L lenght)?

Title: Re: MOSFET resistor
Post by raja.cedt on Nov 20^th, 2009, 7:37am

if you some what resistance (with some non linearity) use transistor in triode region, and if you want good linearity use symmetric load (simply search in Google..you will get john mennatis pap in self bias plls)

Thanks,
Rajasekhar.

Title: Re: MOSFET resistor
Post by buddypoor on Nov 20^th, 2009, 8:22am

Shlapenka wrote on Nov 20^th, 2009, 7:25am:

Greetings,

what makes a MOSFET transistor act as a resistor? Is it W>L (W lenght more than L lenght)?

Each FET, indeed, is a resistor!
It consists of a channel which can lead an electrical current if you apply a voltage across the channel - and that,by definition, is a resistance.
The only (but important) difference to an ohmic resistor is the fact, that there is a quasi-linear relationship between voltage and current only within a limited voltage range (some tenth of volts around zero).
More than that, the value of this resistance can be controlled with the gate voltage.

Title: Re: MOSFET resistor
Post by Shlapenka on Nov 21^st, 2009, 2:16am

thank you all for info :)