VRef - LM4040 vs LM336

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I'm working on a design that uses 6x of the classic Jung Voltage Clippers to block DC voltage greater than +2.5V.



They each require a +2.5V VRef where I have a choice of A) setting up a single LM-336 SOIC buffered by an SOIC Op-Amp and running all 6x VRefs off of that (or perhaps off multiple op-amp buffers as the current draw requires)... or B) using a single SOT-23 LM-4040 for each clipper.

Both methods work and I can see potential advantages/disadvantages of both approaches - so I was hoping some people here might be able to offer some advice on the best approach.

Op-amps are powered by +/- 12V, input signals to clip will be between 0-10V and 1Hz to 10KHz.

[Edit] - Trying to keep current draw and long/complex PCB traces to a minimum are both priorities here.
Thanks!

 

[KlausST]

Hi,

I don't see a problem to use one buffered ref.
But the load at the Ref voltage is switching, to stabilise it I recommend to use RC bypass to avoid ringing and coupling to the other channels..

Tho outputs of each left side opamp will saturate at positive voltage during clipping. The output will saturate and the difference voltage at it's input also is big and thus the input stage will saturate also.
Both leads to time delay and coming out of clipping state will be delayed and distorted a little.

If possible try to avoid opamp saturating. Some Opamps may suffer from phase reversal when the inputs are near supply rails.
Some Opamps have limited differential input voltage range...
Consider this when selecting opamps.

Klaus