Inverting v Non-Inverting Amplifiers

Thread Starter

b0mbst3r

Joined Oct 13, 2016
5


Above is an example of an Operational Amplifier.

Anyone able to explain how better gains are achieved from Inverting Amplifiers than from Non-Inverting Amplifiers, could someone please shed some light on this please, thank you in advance.
 
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#12

Joined Nov 30, 2010
18,224
For any gain I can design into an inverting op-amp circuit, I can design that into a non-inverting op-amp circuit.
This holds true until you get to the frequency or slew rate limit of the chip, at which point, I don't know which one wins.
So, for most practical purposes, your question is false.

If you're going to arrive at a difference in capabilities, you're going to have to narrow down the question to some conditions or requirements besides merely "inverting vs non-inverting".
 

crutschow

Joined Mar 14, 2008
38,484
One difference in gain is that an inverting amp can have a gain of less than 1 whereas the minimum gain of a non-inverting amp is 1.
But both configurations can achieve essentially the same gain as determined by the feedback resistors.

The other difference is in the bandwidth.
The bandwidth of a non-inverting amp is the GBW of the op amp divided by the circuit gain (GBW is the gain-bandwidth product of the op amp).
The bandwidth of an inverting amp is the GBW divided by the (gain+1).
 

#12

Joined Nov 30, 2010
18,224
Wally thought of the "less than one" gain which I completely disregarded and provided the math showing that the non-inverting configuration has a small advantage in the frequency limit end of the application.
better gains are achieved from Inverting Amplifiers
I don't think so.
 

crutschow

Joined Mar 14, 2008
38,484
the non-inverting configuration has a small advantage in the frequency limit end of the application
Actually the biggest bandwidth advantage occurs for low gains where, for example, the bandwidth for a gain of +1 is twice the bandwidth for a gain of -1.
 

crutschow

Joined Mar 14, 2008
38,484
Anyone able to explain how better gains are achieved from Inverting Amplifiers than from Non-Inverting Amplifiers, .........
If you are referring to the difference in gain that MrChips showed above, it's basically that the non-inverting amplifier has the input signal added to the amplifier gain of Rf/Rin thus giving a total gain of 1+Rf/Rin.
(And that's why the gain of a non-inverting amp can never be less than 1.)
 

hp1729

Joined Nov 23, 2015
2,304


Above is an example of an Operational Amplifier.

Anyone able to explain how better gains are achieved from Inverting Amplifiers than from Non-Inverting Amplifiers, could someone please shed some light on this please, thank you in advance.
What did you read that suggested there is a difference?
 
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