level shifting circuit

Thread Starter

MAINAHNOUD

Joined Jul 24, 2019
67
i produced triangular wave from oscilloscope in protus. Then i enter this signal in level shifting circuit, to make it all in positive part, to can use it aas input for arduino. But when i simulated it, shifting level doesn't occurred and the triangular signal as same as signal which from level shifting circuit ( there isn't any change) so why should i do to reach my goal?
1585839117257.png1585839206013.png
 

crutschow

Joined Mar 14, 2008
34,285
For that circuit you would need a negative voltage going to R12, instead of ground, to provide a positive level shift.
How do you expect it to shift otherwise?

A nit: It's easier to follow a circuit diagram if the lines don't have unnecessary jogs, as yours does.
 

dl324

Joined Mar 30, 2015
16,846
What does this mean?
1585839761043.png
Are you applying an input on that resistor?

Your schematic is atrocious. It would be much easier to read if you drew it more conventionally.
 

ci139

Joined Jul 11, 2016
1,898
basically your design works but make all 4 resistors equal
... or otherwise the gain would affect the level
 

Thread Starter

MAINAHNOUD

Joined Jul 24, 2019
67
For that circuit you would need a negative voltage going to R12, instead of ground, to provide a positive level shift.
How do you expect it to shift otherwise?

A nit: It's easier to follow a circuit diagram if the lines don't have unnecessary jogs, as yours does.
i put -9v on it but also doesn't change
 

Audioguru again

Joined Oct 21, 2019
6,674
The schematic has many parts hidden behind the grid. Please turn off the grid.
The schematic has parts so far apart that they are all over my neighborhood. Why?

The output will be more positive if you add a positive voltage to R10.

Your circuit attenuates the signal. Then it does not need R12, and R11 and C8 should be a piece of wire.
 

Thread Starter

MAINAHNOUD

Joined Jul 24, 2019
67
The schematic has many parts hidden behind the grid. Please turn off the grid.
The schematic has parts so far apart that they are all over my neighborhood. Why?

The output will be more positive if you add a positive voltage to R10.

Your circuit attenuates the signal. Then it does not need R12, and R11 and C8 should be a piece of wire.
Indeed I put 9v on R10.
Do you mean that I should remove R11 and R12? Also, I can't understand what should I do for capacitor?
 

Audioguru again

Joined Oct 21, 2019
6,674
Yes, remove R11, R12 and C8. Connect pin 4 to pin 1 making the opamp a voltage-follower. R9 and R10 can vary the attenuation and amount of level shift.
I looked up your TS951 opamp. Its maximum allowed total supply is 14V but you are destroying it with 30V! Then your simulation software did not read its datasheet and I don't think you did either.
 

ci139

Joined Jul 11, 2016
1,898
you didn't look the TS951 specs — it's Vs is +12V (±6V)
sometimes . . . when the op amp is "unipolar" supply one "they" expect the Vss being the GND (not a rule - but a possibility if it still won't work after Vs adjustment)
 
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Thread Starter

MAINAHNOUD

Joined Jul 24, 2019
67
Yes, remove R11, R12 and C8. Connect pin 4 to pin 1 making the opamp a voltage-follower. R9 and R10 can vary the attenuation and amount of level shift.
I looked up your TS951 opamp. Its maximum allowed total supply is 14V but you are destroying it with 30V! Then your simulation software did not read its datasheet and I don't think you did either.
i made the simulation as you told, but there isn't any change (no shifting occurred)
1585907644951.png
 
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