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interchanging of nmos and pmos?

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abhineet22

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what happen if we interchange nmos and pmos in inverter?
 

aravind

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the above is not working for me
can give explaination what it has?
 

nagula suresh

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you will get an weak high and weak low.
means u r high is vdd-vthinstead of vdd.
low is vth instead of zero.
 

pd

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Hi
In that case u will get the inverter not working at all as for all input voltages if u look from the out put node u will see infinite impedance as both transistors will be off. Hence u will get funny behaviour due to noise pickups riding on them.analyse it properly and post agail if u r not able 2 understand it still now.
regards
pratap
 

rogger123

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hi
the inverter acts like a weak buffer. with a reduced noise margin/ output voltage swing.
H= Vdd -Vthn
L= Vss + Vthp

Reasono for this is Body effect .. look it up in google.

hth
cheers
rogger
 

shankarmit

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if u interchange nmos and pmos

your logic high changes from VDD to VDD-Vt
your logic low changes from VSS to VSS+vt..


See Rabey digital integrated circuits chaper 5 CMOS inverter.



Regards
Shankar

Added after 6 minutes:

Thats a cool website.. useful for many begineers in vlsi....
Thanks

Regards
Shankar
 

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