What is a zero-span circuit and how does it work?

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What exactly is a zero-span circuit? How does it work?
 
bos1234 said:
What exactly is a zero-span circuit? How does it work?

Do you mean like gain and offset adjustments in an amplifier?

What is the context of your question? Or did you just hear the term someplace and were wondering what it meant?
 
For example like this

Input range 100mV to 400mV and output Range is -10V to 10V. And it says design a zero-span ckt,

edit:changed input range from 40mV(mistake) to 400mV
 
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I haven't heard the trem "zero-span" before, but it probably means two different adjustments.

They want 100 mV (DC) to produce -10 volts out and 40 mV (DC) to produce +10 Volts out.

So, the input signal varies by -60 mV and the output signal varies by +20 Volts so you can work out the gain (and whether the output is inverted).

Also, a DC offset would be involved.
 
ok. I am to design a ckt. where the inputs range from 100mV to 400mV and the output ranges from -10V to 10V. I have attached my workings and a final design of the op amp ckt. Am I on the right track?

Handwritten derivation on lined paper: input range 100mV to 400mV mapped to output range -10V to 10V, with the line equation y = mx + b, solved values m = 66.66 and b = -16.66, a graph of O/p against I/p through (0.1, -10) and (0.4, 10), and the result Vout = 66.66 Vin - 16.66.


Handwritten notes on paper showing a summing amplifier formula V0 = -(Rf/R1 V1 + Rf/R2 V2), a comparison of ratios with Rf = 34k and R2 = 510 ohm, and a red-annotated op-amp circuit with R1 = 30.6k, R2 = 510 ohm, Rf = 34k, a 15V input and input V2.
 
The input voltages were 100 mV and 40 mV.

I think you are using 400 mV.

I got a gain of 333.
 
vk6kro said:
The input voltages were 100 mV and 40 mV.

I think you are using 400 mV.

I got a gain of 333.

Sorry that should be 400mV. I have edited the post above.
 
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100 mV gives -10 V out
400 mV gives +10 V out

So, should you be using an inverting amplifier?