Help with hw problem (op amps)

[tontod]

I'm taking an EE class after a number of years, and dont remember this material. It is about an output response of an op amp

"A standard inverting amplifier with gain of -10 is designed where the effects of the op amp input and output impedances may be ignored. The op amp has DC gain a0 = 10^5 and two break frequencies which are f1 = 1.5Hz and f1 = 1500Hz. For a unit step input, find the output response of the amplifier in the time domain. (Hint: Use the Laplace transform starting with the two-pole model of the op amp corresponding to the given data.)"

I just dont remember Laplace at all. If anyone can even give me general ideas/hints to proceed, that would be great also, thanks. Feel free to PM me regarding this problem.

Thanks.

 

[WhoBeDaPlaya]

I guess it depends on the unity gain freq / gain-bandwidth product and the corresponding phase margin. Since the problem is using a very small Beta (0.1), the phase margin may very well be sufficient (>= 45deg).

The time response of a unit step will have varying degrees of ringing and overshoot depending on the phase margin. 45 deg = max ringing, overshoot + settling time, 60 deg = optimal, >60 deg = no ringing + overshoot, but the response gets increasingly underdamped (ie. longer settling time).

 

[Oscar1613]

Originally posted by: WhoBeDaPlaya
I guess it depends on the unity gain freq / gain-bandwidth product and the corresponding phase margin. Since the problem is using a very small Beta (0.1), the phase margin may very well be sufficient (>= 45deg).

The time response of a unit step will have varying degrees of ringing and overshoot depending on the phase margin. 45 deg = max ringing, overshoot + settling time, 60 deg = optimal, >60 deg = no ringing + overshoot, but the response gets increasingly underdamped (ie. longer settling time).

you are waaaaay over thinking this

OP, if you're lost on Laplace, then i suggest you start reviewing it and how to get a laplace system from a circuit

 

[tontod]

OP, if you're lost on Laplace, then i suggest you start reviewing it and how to get a laplace system from a circuit

Ok, can I get started without using Laplace?