Re: op-amps with wide open-loop bandwidth ?
- From: kensmith@xxxxxxxxxxxxxxx (Ken Smith)
- Date: Sat, 18 Mar 2006 18:46:21 +0000 (UTC)
In article <Ku6Rf.5141$wQ6.4925@xxxxxxxxxxxxxxxxxxxxxx>,
Dave Moore <valveless@xxxxxxxx> wrote:
Hello,
Anyone know of any op-amps with
open-loop bandwidth in excess of 20KHz ?
I just ran through all the posts that seemed be on topic and there seems
to be tqo issues that were missed.
When OP-AMP makers specify the slew rate of an op-amp they are only giving
you the extreme case. As you get near the slew rate limit, many op-amps
start to become seriously non-linear.
The gain of the early stages in the op-amp decreases as you get near the
slew rate limit. This pushes up the low order harmonics.
The other issue has to do with the common mode input voltage. Many
op-amps (perhaps all) have an extra non-linearity when the input section
has a common mode swing on it. IME, op-amps are better than their
specifications would imply when used in inverting mode. It is likely that
this varies enough from op-amp to op-amp that you could notice the
difference if the op-amp's specs aren't quite good enough for the
suggested circuit.
--
--
kensmith@xxxxxxxxx forging knowledge
.
- Follow-Ups:
- Re: op-amps with wide open-loop bandwidth ?
- From: Dave Moore
- Re: op-amps with wide open-loop bandwidth ?
- References:
- op-amps with wide open-loop bandwidth ?
- From: Dave Moore
- op-amps with wide open-loop bandwidth ?
- Prev by Date: Formulas for this circuit?
- Next by Date: Re: op-amps with wide open-loop bandwidth ?
- Previous by thread: Re: op-amps with wide open-loop bandwidth ?
- Next by thread: Re: op-amps with wide open-loop bandwidth ?
- Index(es):
Relevant Pages
|
