Op amp Comparator activated by NTC-Thermistor

[Teknolog]

I want to make a circuit using the following components:

* 9 V battery
* TL064 op amp (as a Comparator)
* NTC-Thermistor 10 kΩ
* LED, forward biased at 2.7 V
* Resistors (I have lots so can pretty much use anyone)

I want to build the circuit so that heating up the NTC-Thermistor with two fingers (which make it go to about 7.14 kΩ) will activate the TL064 op amp and make it switch and make the light of a LED start to shine.

I need help with the Comparator, i.e. how should I connect to make it behave the way I intend?

Here's a picture of the TL064 op amp, where you can see the connections:



Which connections should I connect into the circut?

Also attached: Data sheet for TL064: View attachment nrTL061-to-TL064_e.pdf

Help is appreciated

 

[crutschow]

What supply voltage(s) do you want to use?

 

[Teknolog]

9 V - Nine volts

 

[crutschow]

Below is a bridge circuit that should do what you want.

I didn't have a TL064 in my model library so I used an op amp that was close. You should be able to use the TL064.
U2 is a pot so you can adjust the trip point.
R3 determines the current through the LED. You can change it's value to get the desired LED current.
R5 adds some hysteresis to the trip point so it doesn't oscillate.