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Hello Forum,
I have a voltage changing slowly against response to a sensor from
10V----->5V . I have 5V single supply OPamp , now how to scale it down to 0V----->5V .
Thanks
Hi ,
The Opamp I have is OPA2335 , powered with 0V and 5V . The signal I get is reverse 10V------>5V (it can be 5V---->2.5V with a divider) .But even if I subtract that I get a -Ve sign? which cannot be handeled .
Thanks
hi,
Say you used the INV of the OPA, with a 2:1 divider so thats +5V to 0V
and if you made the OPA *1.
Input +2.5V into the NI of the OPA.
So for 0V inp you would get +5V out
and for +5Vinp you would get 0V.
Is this what you want.?
Hi,
I am afraid I dont follow you . Do you say to use the difference amplifiers NON-INV input to be heald at 2.5V ,and the INV should be fed the input signal? . If thats the case after divider I get 5V----->2.5V , and when subtraction on the higher side is done I get 2.5-5=-2.5V ? .
Thanks
Here you go.Hello Forum,
I have a voltage changing slowly against response to a sensor from
10V----->5V . I have 5V single supply OPamp , now how to scale it down to 0V----->5V .
Thanks
hi,
The INV gain is -1 , the NI gain is 2
Dont forget the 10V signal is via a resistive divider 2:1 so it +5V to 0V
Here you go.
That's also my interpretation. See my previous post.Mike,
Unless Im misreading the OP.
The OP wants to transpose 10 > 5V to 0 > 5V...??
The common mode range of the OPA2335 is -0.1V to +3.5V.
The transfer function is
Vout=10-Vin.
This must be accomplished within the common mode range.
See below.
It could be accomplished with one op amp, but the resistor values get pretty funky.
That's also my interpretation. See my previous post.
Excellent!Here is my no funky resistor single OpAmp solution.
The common mode range of the OPA2335 is -0.1V to +3.5V.
The transfer function is
Vout=10-Vin.
This must be accomplished within the common mode range.
See below.
It could be accomplished with one op amp, but the resistor values get pretty funky.
Mike posted an elegant solution.Hello,
Also, if a small error is acceptable and the loading wont bother the sensor,
then making R3=2k and R4=1k and eliminating U1 also works ok. That gets us
back down to one single op amp.