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<DIV dir=ltr align=left><SPAN class=529444103-30122020><FONT color=#0000ff
size=2 face=Arial>Most of the common opamp circuit configurations also act as
buffers. What that means is that the opamp will supply as much current as
is required to maintain the desired voltage regardless of the downstream
impedance.</FONT></SPAN></DIV>
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<DIV dir=ltr align=left><SPAN class=529444103-30122020><FONT color=#0000ff
size=2 face=Arial>However, if there is something like a diode inbetween the
opamp's output and the destination, then you have to be very careful. For
example, the classic two-diode opamp rectifier does not buffer, and must be
followed with a buffer generally. This is one of those areas where it is
easy to make a design mistake, and then when your design doesn't do exactly what
it is supposed to, you have a forehead-slapping moment when you realize that you
have inappropriately taken opamps for granted.</FONT></SPAN></DIV>
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size=2 face=Arial></FONT></SPAN> </DIV>
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<DIV dir=ltr align=left><FONT size=2 face=Tahoma><B>From:</B> Synth-diy
[mailto:synth-diy-bounces@synth-diy.org] <B>On Behalf Of </B>Kristian
Blåsol<BR><B>Sent:</B> Tuesday, December 29, 2020 6:41 AM<BR><B>To:</B>
synth-diy mailing list<BR><B>Subject:</B> [sdiy] Buffered
question<BR></FONT><BR></DIV>
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Non-UBC Email]</SPAN></SPAN></SPAN>
<DIV dir=ltr>Hello,
<DIV><BR></DIV>
<DIV>A question about opamp buffers or voltage followers. So one of those
circuits makes sure that whatever you plug in to the output of the buffer
wont affect whatever you have on the input of the buffer... right?</DIV>
<DIV><BR></DIV>
<DIV>But there are so many different circuits you can make with an opamp, is
there any of those that in itself IS a buffer, or do ALL other opamp circuits
need buffering after it for the output to not affect the input?</DIV>
<DIV><BR></DIV>
<DIV>For example: a comparator, isnt that already buffered in itself? Since the
output is either ground or +v?</DIV>
<DIV><BR></DIV>
<DIV>And how about a mixer/summing amplifier, op-amp as an amplifier, high and
low pass filters.</DIV>
<DIV><BR></DIV>
<DIV>Im thinking so I dont put a buffer on an already buffered
signal... :)</DIV>
<DIV><BR></DIV>
<DIV>Thanks in advance,</DIV>
<DIV>/Kristian</DIV>
<DIV><BR></DIV>
<DIV><BR clear=all>
<DIV><BR></DIV>-- <BR>
<DIV dir=ltr class=gmail_signature data-smartmail="gmail_signature">
<DIV dir=ltr>
<DIV>---</DIV>
<DIV>Kristian Blåsol</DIV>
<DIV><BR></DIV></DIV></DIV></DIV></DIV></BODY></HTML>