16f877 with LM335 problem

[flotulopex]

If you are just connect the sensor to the PIC directly, your useful range will be limited (0C-100C is from 2,7315 to 3,7315 Volts). I suggest to use opamps and extend the range of the sensor from 0C->0Volts to 100C->5 Volts.

Can anyone please help me with a schematic on how to achieve what Ioannis is suggesting or is the example below not far away from what I'm looking for?

How do I "electronically" rescale 2,7315Volts to an ideal "0V" and/or a 3,7315Volts to an ideal "5V"?

I don't know...

As I'd like to use my sensor to control a freezer, the temperature range I need goes from -30°C to +30°C.

I found quite some info, for example here and I've already ordered some LM358 opamps to build this circuit.

It looks like this circuit will output 0V at 0°C and 1V at 100°C. It is still "loosing" 4 precious volts, isn't it?

How can this circuit be modified to, again ideally, match something like -30°C = 0V and +30°C = 5V?