NotedPeeps you are talking to a man who is incapable of opening and reading a textbook. I have brought this point up in his last thread, the one dealing with linearity of Linear Time Invariable systems.
Look. You do not know me and I do not know you. In that topic you used some words that I decided to ignore. Now you again show a bad attitude and continue to offend me even though I did not offended you in any way. This shows that you do not have those 7 years from home when you should have learned to respect other people.Peeps you are talking to a man who is incapable of opening and reading a textbook. I have brought this point up in his last thread, the one dealing with linearity of Linear Time Invariable systems.
In general, a MOSFET can conduct in either direction. Whichever drain/source terminal is at the lower potential is the source terminal and the gate-source voltage is therefore the voltage between the gate and the lower-potential terminal.So we have the same equations.
I mean, yes, it seems logical. The MOSFET does not care how you name its terminals. The electrons could go both ways through the channel in the same way.
Thanks.
And I suppose it does matter how you name the terminals if there is a built-in diode between the drain and the source. So, in this case, the MOSFET is constraining the electrons to flow only from source to drain (conventional current from drain to source).
As a rule, what happens in one thread should be allowed to stay in that thread.Peeps you are talking to a man who is incapable of opening and reading a textbook. I have brought this point up in his last thread, the one dealing with linearity of Linear Time Invariable systems.
I understood this. And you say that if the bulk is connected to a sufficiently low-potential supply then we might have symmetric layout. I saw somewhere that the bulk is usually connected to 0V. So in this case the layout should be symmetric and the ids vs vds characteristic in the fourth quadrant looks the same as the one in the first quadrant. Right?In general, a MOSFET can conduct in either direction. Whichever drain/source terminal is at the lower potential is the source terminal and the gate-source voltage is therefore the voltage between the gate and the lower-potential terminal.
But this is assuming a symmetric transistor layout.
So in discrete tranzistors the bulk is tied to source. Thus there is a parasitic diode (because of the asymmetry) from bulk/source to channel, i.e from source to drain!? by extension like the above posts say.There is a parasitic diode between the body (bulk) region and the channel, which is indicated in the full MOSTFET transistor symbol.
View attachment 95508
In the case of an NFET, the bulk is the anode and the channel is the cathode. The bulk is usually either connected to the source terminal (in which case the layout is no longer symmetric) or to a sufficiently low-potential supply (in which case the layout might remain symmetric). In discrete transistors the bulk is almost always tied to the designated source terminal. Even so, the transistor will still function with negative Vds provided the reverse potential is kept small enough not to substantially turn on that parasitic diode.
by Jake Hertz
by Jake Hertz
by Jake Hertz