Temperature Controlled LEDs using LM35

I'm working on the temperature controlled LED project from the site

 

https://circuitdigest.com/electronic-circuits/temperature-controlled-le…

 

and I am running into the problem of only the RED LED glowing and not the YELLOW when the case should be the YELLOW LED is glowing and the red when heated. I have the circuit hooked up as it is described in the instructions.

Aswinth Raj

  Joined August 16, 2016      1000

Tuesday at 12:29 AM

Use a multimeter to check if the yellow LED is in working condition. 

Also what do you mean by this line?

when the case should be the YELLOW LED is glowing and the red when heated.

J

Justin Jones

In reply to by Aswinth Raj

  Joined October 23, 2018      6

Tuesday at 11:10 PM

I mean that the red is glowing as soon as I hook up the power supply the red is heated. Instead of red the yellow should be.

A

Abhishek

  Joined May 19, 2015      402

Tuesday at 03:13 PM

Most probably the issue is with the reference voltage of LM358, try adjusting the reference voltage by rotating the potentiometer till the point where yellow LED starts glowing.

Also check the connections again, specifically with LM358.

J

Justin Jones

In reply to by Abhishek

  Joined October 23, 2018      6

Tuesday at 11:10 PM

I've checked both of those. I will try to rebuild the circuit and see if anything changes.