How can I attenuate B4 a buffer without loading it down?

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Ethan

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I'm trying to design a simple metering circuit. The amp output can swing a bit higher than the 5532 being used as a buffer input to the meter circuit. Using a simple voltage divider (even high values like 100k/100k) before the buffer would kind of defeat the purpose of the buffer wouldn't it? Is there a better way to do this so that the driving amp still sees the gargantuan input impedance of the 5532 and not the load of the voltage divider resistance?
I guess practically speaking, just about any amp wouldn't care about a 100k load, but I keep thinking there must be a better way to do this.
 
I don't know, does it defeat the purpose of the buffer? what is the output-Z of the driver stage?

[quote author="Ethan"] Is there a better way to do this so that the driving amp still sees the gargantuan input impedance of the 5532 and not the load of the voltage divider resistance?[/quote]

well, you could use an even higher input-Z opamp like a TL072. then size the attenuator resistors against the input capacitance of the amp inputs, so that you start to roll off at about 20k. you'll have to do a little math to figure out how much R that will allow.

is the signal balanced?

mike
 
Thanks for the reponse Mikep.

I don't know, does it defeat the purpose of the buffer? what is the output-Z of the driver stage?
Well, I do realize the answer to the first question is a practical no, it's an opamp output with NFB, so the output Z of the amp is about an ohm. The current solution will work fine, but I was just curious if I could learn of a more elegant solution(I'm still a noob, so I always suspect there would be a better method than what I think up)...

is the signal balanced?
No, Single-ended
 
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