Hi,
When considering speed of OPAMP, there are two parameters of slew rate and bandwidth. My gut feel is bandwidth is a very clear concept, because it is based on the solid Fourier theory. But I have no sense of slew rate. Is there inherent relation between them? Which one is more effective in a certain context?
Slew rate is dependent on the current available at an internal stage to charge and discharge a capacitance. It will set the large signal frequency response.
So for large signal, the transition speed of OPAMP is limited due to slew rate rather than bandwidth? In other word, slew rate is a lower limit than bandwidth for large signal?
No, you can´t "nullify" the slew rate.
The value of SR is determined by the compensating capacitor within the opamp.
If you need higher SR values, use opamps with external frequency compensation capability and compensate only as large as necessary for the corresponding gain - or use current feedback amplifiers.
No, you can´t "nullify" the slew rate.
The value of SR is determined by the compensating capacitor within the opamp.
If you need higher SR values, use opamps with external frequency compensation capability and compensate only as large as necessary for the corresponding gain - or use current feedback amplifiers.
We have already had this conversation two months ago. There are ways to increase Slew-rate beyond the recommendations that LvW gives. you can read the converstion here:
We have already had this conversation two months ago. There are ways to increase Slew-rate beyond the recommendations that LvW gives. you can read the converstion here:
Hey, PaloAlto !
Of course, you are right. However, I think we have to distinguish between two cases:
1.) Determining the slew rate SR by modifying the internal structure of the opamp
2.) Change of the SR for a commercial opamp from the stock.
The reference mentioned by you refers to case 1) whereby, most probably, the question from steadyj belongs to case 2.) .