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Voltage Dividing Oscillating Voltage

tb303wpf1

Aug 26, 2018
3
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Aug 26, 2018
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3
Hey guys,
I have a source voltage from a signal generator that's going from 3v to 4v to 3v to 4v in a triangle waveform. The device I am hooking the source to needs to go from 0.1v to 1.1v to 0.1v to 1.1v. Could I use a voltage divider or pot to cut the source voltage down, while still maintaining the 1v up and down oscillation? Or would there be a better way to achieve the same effect?
Sorry for the noob question. And thank you all for any help!
 

Nanren888

Nov 8, 2015
622
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Nov 8, 2015
Messages
622
Your suspicion is correct. If you use a voltage divider, it will also divide the triangle waveform amplitude.
Tell us about the input that has to see the 0.1 to 1.1 volt triangle wave.
Particularly do you know the impedance? That is, what sort of load will it be?
Also, if you need some active components to shift the voltage, what sort of components do you know about?
If you use an active device for the shifting, it may need power. Is there a power supply, a regulated voltage rail, like 5 volts or similar involved, one that might power the active device?
In short can you share a little more about what you're looking for and have to work with?
 

tb303wpf1

Aug 26, 2018
3
Joined
Aug 26, 2018
Messages
3
Sure, thank you so much for the reply!! I am using a signal generator to make a triangle wave that I'm using to control and old analogue radio. Everything is battery powered. I've done this with a few other tuners where the voltages needed to go from 2v-6v triangle wave. The load is very minimal. I'll test it when I get home but if I had to guess I would say about 0.5a.
This particular tuner needs the voltage to be 0.1v-1.1v, I changed the quad op amp to the LM324 because it had a min operating voltage of 3v. And I have tried changing the caps on the circuit to slow the speed down. Which worked. And no matter what combination of resistors I use I cannot get the bottom voltage down to 0.1.
I can adjust it to very easily go from 2.0v-3.0v. And so If I can attenuate that down, while maintaining the triangle width, then I should be home free.
Thank you again so so much for the help. I really appreciate it more than you know.
 

WHONOES

May 20, 2017
1,217
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May 20, 2017
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1,217
It should not be to difficult to devise a level shifter to do the job. What frequency are you using?
 

tb303wpf1

Aug 26, 2018
3
Joined
Aug 26, 2018
Messages
3
It should not be to difficult to devise a level shifter to do the job. What frequency are you using?
I'm not sure the exact frequency until I test it when I get home. But I replaced the ceramic 47nf caps with 100uf electrolytic caps. That slowed the frequency down to a crawl which is what I needed. I'll test it and give you an exact number. Thank you so much my friend!
 
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