# Project Help - Design of an op-amp circuit.

Discussion in 'The Projects Forum' started by Ricky Sum, May 6, 2016.

1. ### Ricky Sum Thread Starter New Member

May 6, 2016
13
0
Hi Everyone I got a project but I dont understand and also where to start with.

DESIGN OF AN OP-AMP CIRCUITS

Given that the pressure sensor produces an output voltage (Vs : sensor output voltage) according to the equation Vs = (P x 0.131 )+ 1.683. This equation can be expressed in
terms of pressure (P) versus sensor voltage (Vs). ie. P = (Vs - 1.683)/0.131 You are to design the amplifier circuit for this sensor using any combination of
inverting amplifiers, non-inverting amplifiers, summing amplifiers together with a 1V
reference voltage source. The two input signals of this circuit are sensor voltage (Vs ) and an 1V reference
source (Vref ) and the circuit should produce an output voltage (Vo) indicating the pressure (psi) according to the equation Vo = P (psi)
i.e When P = 0 psi , Vo = 0V and P = 10 psi, Vo = 10V. P = -10 psi, Vo = -10V.

2. ### Bordodynov Active Member

May 20, 2015
600
175
I decided to have fun.
See

Ricky Sum, frpr666 and wayneh like this.
3. ### Dodgydave Distinguished Member

Jun 22, 2012
4,779
707
What sensor are you using, which op amps, voltage, pressure range?

Last edited: May 7, 2016
4. ### Ricky Sum Thread Starter New Member

May 6, 2016
13
0
Normal pressure sensor

Hi, are this is the step of doing this project.

Last edited by a moderator: May 7, 2016
5. ### dannyf Well-Known Member

Sep 13, 2015
1,602
315
It looks like a summer, and a gain stage, at a minimum.

All you need to do is to break that equation into formats that can be handled by a typical opamp block.

6. ### Ricky Sum Thread Starter New Member

May 6, 2016
13
0
How can break the equation

7. ### Ricky Sum Thread Starter New Member

May 6, 2016
13
0
How do you break the equation?

Sep 17, 2013
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9. ### AlbertHall Well-Known Member

Jun 4, 2014
1,379
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This pressure sensor reads down to -10psi? Given that a vacuum is 0psi, how do you get lower pressure than that?

10. ### wayneh Expert

Sep 9, 2010
11,896
2,845
The "g" for gauge in psig is often dropped. Endless confusion versus psia, "a" for absolute.