Anyone know how to use the results of a Freescale MPX4250A pressure sensor?

I am getting the value 368 as Vout and my Vs is 4.96V.

The equation Vout = Vs*(0.004 x P-0.04) is from the datasheet where P is measured in kPa.

Thanks

Anyone know how to use the results of a Freescale MPX4250A pressure sensor?

I am getting the value 368 as Vout and my Vs is 4.96V.

The equation Vout = Vs*(0.004 x P-0.04) is from the datasheet where P is measured in kPa.

Thanks

Hey yo!

Just connect the output pin via a 10k resistor to an analog-in pin (ADC) and use analogRead() to read it?

http://arduino.cc/en/Reference/AnalogRead

Cheers, Arne

clearly, analogread is being used.

I show how to access a similar analog output pressure sensor on my website...

look here for some sample code--> http://pwillard.com/?p=31

I try to work backwards from some roughly known standard, like atmospheric pressure at about 101kPa, and see if the numbers fit.

Then, try adding 300mm of water pressure, then 600mm and so on.

Yup, 368 looks pretty good.

oh - u wanted to know how to use the results of a voltage measurement?

just solve the equation to P:

P = (V_{out}/V_{s} + 0.04) / 0.004

the results of analogRead() (=X) r converted as follows:

V_{x} = (X+0.5) * V_{ref} / 1024

example with Vref=5V and Vref=4.96V:

100.69kPa = ((368.5*5V/1024) / 4.96V + 0.04) / 0.004
99.97kPa = ((368.5*4.96V/1024) / 4.96V + 0.04) / 0.004

-arne

Thanks everyone! I got it working!