7 segment display thermometer

I have a few LM34's and 7 segment LED's and am wanting to make a thermometer in a 12 vdc environment. I am very new to electronics and would like some help. If anyone knows of an online tutorial that can help me it would be much appreciated.

 

Well really what you need is help building a voltmeter and controlling the display of it. The output from the LM34 is simply a voltage and you could use an op-amp (or 2) to produce whatever offset and scale you need for your voltmeter, so that it reads temperature.

 

If you are wanting to build a circuit, you will need more parts (as wayneh has said,) but if you are just wanting to use your LM34 to display the temperature, see this. http://forum.allaboutcircuits.com/showthread.php?t=50951

 

Yes, this is what I wanted help with. I saw a max138 chip on another site and thought I can use it. But with potential temperatures of over 200 I think something different should be used.

I did see the harbor freight temp sensor. I was thinking of using it but I need to see the display in very low light. Plus I want to challenge myself and build it from scratch.

 

The typical temperature I will be reading will be between 80 - 230 degrees.

 

No worries at 200°K !

 

Not really understanding...the temps I would like toes sure are in fahrenheit...this would be what the LM34 made for correct?

 

That's correct.

In essence, what you are planning to do is make a digital voltmeter, which will require a specialized IC like the ICL7107 or a programmed micro-controller. To attempt one with individual components would be a very difficult project.

 

Sorry about that. I guess I just forget there is a metric system out there.

 

Is this for a car?

 

No, this is for a mobile brew station(Ale's).

 

Are you sure you don't mean a thermostat instead of just a readout?

 

Mobile? Huh?

 

iBrew?

Bob

 

Thanks for your help, I teach home brewing techniques. Some of the events I attend do not have easily assessable power. So I have built my brew station to run on a 12 volt system. Eventually I will want to automate my transfer pumps and sparge system. But this will take time as I am slowly learning about electronics. I know I can easily go out and buy this equipment, but I like building things with my own two hands. Plus I get to learn along the way.