Which gate is normally preferred while implementing circuits
using CMOS logic, NAND or NOR? Why?

Answer Posted / balaji kalluri

if u look at the structure of cmos-nand gate,u cud find the
parallel pmos pull-up transistor configuration whereas in
cmos-nor gate its series config,so the effective resistance
offered by 2-pmos transistors even when they r conducting
due to small Rds (drain-to-source resistance)are smaller in
comparison to the same offered by series pmos in nor
gate..hence the current delivered to the output during HIGH
o/p condition is more for nand gate,due to which it has the
ability to drive more no. of loads of similar type ,thus
offer improved FAN-OUT than cmos-nor gate.
I feel tat this could be the reason..it is true fact as per
WAKERLY text book..but there cud be 'n' no of other reasons
too..think over

thankx..
balaji kalluri

Is This Answer Correct ?    73 Yes 7 No



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