Comments on: An Op Amp Gain Bandwidth Product

By: Adrian S. Nastase

Adrian S. Nastase — Sat, 15 Feb 2020 21:53:04 +0000

In reply to YS Yang. The op amp by itself is a voltage amplifier with high gain. So, GBP refers to voltage gain.

By: YS Yang

YS Yang — Thu, 19 Dec 2019 08:37:36 +0000

For GBP of a OP amp, what is the gain refers to: current gain, voltage gain or power gain? OP amp generally have a high input impedance. So it has a very high current gain. Does this mean it would have a very low band-width?

By: Adrian S. Nastase

Adrian S. Nastase — Sat, 07 Sep 2019 18:46:01 +0000

In reply to Madz M.. Please point to the datasheet that has frequency as a parameter for GBP.

By: Madz M.

Madz M. — Fri, 30 Aug 2019 04:52:00 +0000

Hi,
Question regarding datasheet specs for GBP.
Usually, i observed that op amp datasheets have gain Bandwidth products with test conditions of Av and RL. I believe this means that the product was characterized on these constant gain and RL values which GBP can be calculated by frequency sweep until a -3db is observed on the gain. At this point, the product of the gain and freq is the GBP.
My problem is, i also encountered another datasheet where the test condition is a frequency. So this must also mean that they supply the product with constant freq signal and measure the gain, but how could you apply the -3db requirement to determine that the product is already in roll off if we dont have a constant gain? How do we measure the GBP with constant test frequency?

By: Adrian S. Nastase

Adrian S. Nastase — Thu, 20 Jun 2019 02:54:12 +0000

In reply to Paul G. In the past, if you needed a precision op amp you would have to give up in bandwidth. Nowadays, precision op amps are faster and faster. So, if GBWP is not a concern for your application, then look at the other specs. Choose an op amp that is suitable for your task at hand.

By: Paul G

Paul G — Tue, 21 May 2019 14:22:34 +0000

When shopping for op amps there’s a wide range of GBWP available. It seems like in general the higher the better. Is there any reason or case to intentionally use a low GBWP?

Thanks for the articles.

By: Adrian S. Nastase

Adrian S. Nastase — Sun, 28 Apr 2019 02:16:32 +0000

In reply to Kay. This sounds like a homework, so I am not going to do it for you. Hint: The answers are in this article.

By: Kay

Kay — Tue, 09 Apr 2019 15:52:55 +0000

Please calculate the gain of the op-Amp if no feedback is present
a) as a unit less than ratio
B) as a logarithmic unit
C)at -3dB

By: Adrian S. Nastase

Adrian S. Nastase — Wed, 04 Jul 2018 19:24:59 +0000

In reply to Lav Kumar Yadav. It is commonly used for one-pole compensated amplifiers. Regarding the second question, if this is a one-pole bandpass then, yes, it applies.

By: Lav Kumar Yadav

Lav Kumar Yadav — Sun, 10 Jun 2018 06:28:49 +0000

HI adrian
I want to know is gain bandwidth product is defined only for single pole amplifiers?
and also what if amplifier has bandpass magnitude graph?