Schmitt trigger VS. Inverter

[JackyH]

I have a question regarding the Schmitt trigger . It seems like Schmitt trigger is often used in integrated circuit to obtain a steep signal

But a simple inverter can also do this job, to make the output signal have a steep transition

I want to know more about Schmitt trigger ,normally when do people apply Schmitt trigger instead of inverter?

 

[plusminus]

You use a Schmidt-trigger (S-T) when de input signal is not going directly from 0 to 1 (or 1 to 0 ) but slowly or with a 'bump'. The S-T prefents false data transitions.
See picture:

(input signal)
(output signal without S-T)
(output signal with S-T)

 

[andre_luis]

ST are used when the circuit mix analog with digital signals.
It is very important if you design circuits based on syncronous philosophy.

+++

 

[A.Anand Srinivasan]

schmitt triggers are used when the input is noisy.... i.e. the input may cause multiple transitions if given to a ordinary comparator...

 

[Alan_Nesta]

So every digital input I/O first stage is Schmitt Trigger inverter for noise cancellation.

 

[leo_o2]

Sometimes, the input voltage is not ground or supply level. For inverter, it will be a large quiescient current while it is not the case for schmitt trigger.

 

[joe_chen]

eleminate the noise