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XR2006-Sawtooth Amplitude Control

danadak

Feb 19, 2021
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1) Resistor divider on output (or pot), but then its not buffered. So use a OpAmp
follower to buffer.

2) Zener diode (again output unbuffered) :

1673443402494.png


Regards, Dana.
 

bigkim100

Apr 17, 2013
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Thank you very much Sir, that is excellent. I wasnt certain if a Zener would add unwanted noise. YOU ARE A GOD!!
 

hevans1944

Hop - AC8NS
Jun 21, 2012
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YOU ARE A GOD!!
Dana is a pretty clever engineer, but this site does welcome all visitors (who write in English). Because there are so many international participants here, each with their own perception of who made the Universe and what our purpose (if any) in it is, it does appear that most posters here avoid even mentioning a Supreme Being, or God when making inquiries.

I personally pray to God for guidance (almost) every day and, provided I pay attention, I will usually receive prompt "answers" or "hints" about where to look for an answer. As a last resort, after exhausting all attempts to find answers from observation, memory and training, either from printed books or online using a search engine, I will ask questions in forums such as Maker.Pro. Problem is, vetting those answers can be difficult.

I trust many of the posters who answer questions. but certainly not all of them. @danadak offered the solution you need: attenuate and then follow that with a unity-gain buffer to restore the low-impedance (presumably) of the source.

Every electronic component, in any environment whose temperature is greater than absolute zero Kelvin, will generate some amount of electrical "noise" that is not easily removed because later circuitry that will make changes to the nature of the signal of interest. If this turns out to be a problem, often extraordinary measures must be taken to "eliminate" the "noise problem."

I don't use zener diodes much anymore, not because they are particularly noisy, but because there are better devices made that will provide excellent voltage references that are virtually insensitive to ambient temperature changes over a wide working range.

I have used a string of ordinary, series-connected, forward biased, signal diodes to perform level shifting of roughly 0.7V per diode, as well as clamping a signal to a specific level (usually a power supply rail) to avoid over-driving the next circuit stage. There is always more than one "solution" to a problem. Choose a solution with minimum grief and undesirable side effects that you can afford. And don't forget to actually construct and test real circuits, even if you have a computer to "simulate" your real circuit. All simulations have limitations on how much "reality" they can faithfully simulate. You need to be aware of those limitations, and when and where they apply before accepting any simulation output as gospel.
 

Harald Kapp

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Nov 17, 2011
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Potentiometer + OpAmp (@danadak ' solution #1) allows you to easily adjust the amplitude of the signal to varying needs.
 
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