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7th February 2009, 15:48 #1
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slew rate bandwidth
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?
Thanks,
Steadyj

7th February 2009, 16:59 #2
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increase slew rate
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.

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7th February 2009, 18:10 #3
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slew rate vs bandwidth
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?

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8th February 2009, 04:46 #4
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slew rate and bandwidth
yes

8th February 2009, 08:37 #5
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slew rate and banbwidth
slew rate is large signal, bandwidth is small signal

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8th February 2009, 21:52 #6
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how to increase slew rate
The lousy old 741 opamp has an output of 28Vpp up to 9kHz. Higher frequencies are distorted into trianglewaves with reduced peak voltages.
But it still has plenty of gain up to about 100kHz where its max undistorted output is only 3.5V pp.

12th February 2009, 11:54 #7
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slew rate bandwidth calculation
Is there a way to increase the slew rate...........i mean to nullify the effect of slew rate ??

12th February 2009, 12:33 #8
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slew rate bandwidth
Originally Posted by desperado1
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.

12th February 2009, 14:02 #9
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increasing slew rate
Originally Posted by LvW
https://www.edaboard.com/viewtopic.p...ight=slew+rate

12th February 2009, 14:50 #10
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slew rate vs. bandwidth
Originally Posted by 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.) .

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12th February 2009, 16:41 #11
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bandwidth vs slew rate
You are probably right, I tend to think in terms of IC design

13th February 2009, 07:12 #12
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slew rate effect
slew rate simply means how much ur output is following ur input,bcoz ur output doesn't follow input for high frequency bcoz of circuit complexity
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