why are call the pmos is strong1 and weak0and nmos is weak1

[vamsi_addagada]

why are call the pmos is strong1 and weak0and nmos is weak1 and strng 0?plz tell me reason?any one

 

[vlsitechnology]

My dear friend plz read the text book and come..Don't ask the questions blindly..it is clearly given in Neil Weste,John P uyemura,David A Hodges and so on
Bye

 

[pmaheswara]

Re: why are call the pmos is strong1 and weak0and nmos is we

hey vlsi technolgy, if u don't have interset then don't give reply...u don't have rights to judge the person it is his interest he can do post any question even he knows..

 

[venkat_kvr]

Re: why are call the pmos is strong1 and weak0and nmos is we

why are call the pmos is strong1 and weak0and nmos is weak1 and strng 0?plz tell me reason?any one

NMOS will turn on whn Vgs(Vg-Vs)>Vth, PMOS will turn on whn Vgs(Vg-Vs)<Vth.

Whn NMOS is used to pull down the ouput to Logic-0, Vgs won't change it remains at VDD(input voltage).Since Vdd>Vth NMOS will be on throughout the discharging of output node to logic-0. So NMOS will effectivly pass logic-0.

similarly

Whn NMOS is used to charge the ouput node(source) to logic-1, Vgs won't be same is VDD, it starts to decrease since input voltage is Vgs which is eual to Vg-Vs Vs starts increasing(load capacitance is charging) so whn source voltage(which is same as Vout) reaches VDD-Vt the effective input voltage Vgs will become less than Vth so transistor will turnoff.
NMOS can pass logic-1 upto VDD-Vth which is degraded logic-1.


Same reasons can be applied to PMOS.

Just chk this figures