7 segment pressure gauge help? Modify voltmeter from Projects?

johndeverill

Nov 16, 2004
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Nov 16, 2004
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Hi,

Relating to my other post. I have a pressure transducer that outputs 0-100mV for 0-30psi. What I would like to do is create a 7 segment led (well double/triple) figure type that would display 0-30 for 0-100mV being supplied.

If anyone could point me in the right direction on this one that would be great. Even if you just know a good site that would be fantastic.

Many thanks

John

 
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MP1

Dec 7, 2003
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Look in our projects section for the digital voltmeter project. This sounds like it is exactly what you want.

MP

 

johndeverill

Nov 16, 2004
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Nov 16, 2004
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Hi MP,

I've taken a look and I can see it could display the voltage for me fine. The issue I have is that I want to display 0-30 instead of 0-100mV so that it displays the pressure. Can you point me in the right direction so that I can do the conversion?

Many Thanks

John

 

MP1

Dec 7, 2003
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Hi John,
The data sheet has information regarding resistor changes needed for different ranges. This is a pretty versatile chip.

MP

 

johndeverill

Nov 16, 2004
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Hi MP,

I may have missed the point here, you'll have to excuse me as I'm quite new to electronics but learning......slowly but surely!!

I actually think the input will be 0-330mV for a 0-30psi range off the tranducer. The thing is if i set full scale to be 330mV etc the unit will read 99. What I would like it to read is 30. Can you advise on this?

Many thanks

John

 

johndeverill

Nov 16, 2004
40
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Hmmmm,

Just been thinking and I may have answered my question.

Is it just a matter of changing the resistance to alter Vref so that when the transduer is at full scale the voltmeter is only displaying 30 on the LED's?

Thanks

John

 
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