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logicalman
Feb13-05, 01:48 PM
Who has the guts to do the problems given in the attached pdf file???

I would like the folks competent to solve them to do Prb. 2 and 3.

Thanks!

P.S. few weeks ago I had posted a file related to Op-amps but no fruitful help was gotten from this forum, eventhough I am posting this file.

Hoping I get some good suggestions on these problems.
gnome
Feb13-05, 02:27 PM
Testing to see how many flies you can catch with vinegar?
logicalman
Feb13-05, 03:21 PM
Well anyways, here's what I've thought

In a general Schmitt Trigger figure:

No resistor between Vin and the inverting input.
It has a positive feedback along with a resistor R_3,
The non-inverting input has constant 5VDC input which is V_ref, there is a resistor R_2 between V_ref souce and the non-inverting input.
non-inverting input is also connected to the ground along with the resistor R_1.

As in the fig. in the attached file of schmitt trigger...


Now, V+ depends on V_out. When V_in < V_ref then V_out switches to V+saturation otherwise V-saturation.

and V+(>) - V+(<) = (2 R_123 / 3)
( R_123 eq. of all the 3 resistors)

The thing is what values of resistors shall I use?
and whats the use of output current and the sink current?
ktpr2
Feb13-05, 03:32 PM
You can't have people do your homework for you! Go back to your teacher!
logicalman
Feb13-05, 03:41 PM
if u can't post anything worthwhile then don't b.s. atleast.
logicalman
Feb13-05, 05:02 PM
It *seems* like I am posting way too "advanced" stuff in here.
Curious3141
Feb14-05, 11:38 AM
Logicalman, in your previous opamp thread, I *had* solved one of the problems for you. You didn't post whether you agreed, or even whether it was helpful.

Remember this thread ? http://www.physicsforums.com/showthread.php?t=62098
logicalman
Feb14-05, 04:13 PM
Logicalman, in your previous opamp thread, I *had* solved one of the problems for you. You didn't post whether you agreed, or even whether it was helpful.

Remember this thread ? http://www.physicsforums.com/showthread.php?t=62098

I did the same thing written in that post of yours except the way of finding input impedance.

Anyways, for the problems I've posted over here - I already did them.