Op-Amp temperature controll circuit needed

[scream_er]

Hey guys, I need a circuit to control the temperature using op-amp. I dont want to use any programing since im fairly new to electronics. This is just my 2nd project. I just need to keep a heating strap within a particular temperature and off it manually. Thats all. Any help will be appreciated.

 

[burningmosfet]

Please have a look to the circuit on page 7 fig. 11 on this doc:

**broken link removed**

Use Lt spice (free sw) to simulate the circuit

I forget to tell you that this circuit uses a cheap (altough non linear) NTC thermistor for temperature sensing.

 

[krishna1234]

use a simple comparator for your purpose.

 

[Senthilkumar_rjpm]

Go threw this links. it may help you...
Constant Temperature Circuit
Temperature Alarm with Op-Amp Comparator | Simple Circuit Diagram