Temerature sensor

[JPI]

Hi, I am wanting to make a temperature sensor circuit that only has an output or reading from 30ºC to 50ºC, can anyone give me some pointers.
Many thanks

 

[manish12]

Use LM35 temp sensor

 

[Papabravo]

The first step is to find an appropriate sensor, and there are several different types including thermocouples, and RTD devices. By googling for manufacturers of these devices I'm sure you can find one that meets your needs. The next problem is to develop a circuit to read voltage or current from the sensor. Now the fun part. These devices are usually nonlinear so you have to linearize the values to get temperature. This pretty much implies a microcontroller.

There are also IC's (LM35 and similar) that measure temperature and give a voltage output directly.

How do you think you want to proceed?

 

[ajc]

Hello...
You might want to try an LM35 device for this. This is a little 3 terminal
part in a TO-92 size package. The output from this device will be a
voltage that is directly equal to degrees centigrade.

Something around 10 millivolts per degree C...you will
have to check this, cuz, im not sure.

If you go to National Semiconductors website and look up the
data sheet for this device....you should be able to find some
circuits and configurations for you to try.

I am using an LM34...in the data sheet for this device there is a
circuit for a narrow range of temperature mearsuraments.
Its a smaller range, but it think the smaller range has more
resolution.

Art