Temperature Sensitive Switch, Heat Activated Switch Using CA3140 Op-Amp

Temperature Sensitive Switch is a simple project which operates a relay when the temperature in a particular area goes above a set point.  This circuit is built using CA3140 Op-amp and NTC temperature Sensor.

Input : 12 VDC @ 50 mA
Range : 30 °C to 60 °C
Relay output : SPDT relay
Onboard preset to set the level
Relay On LED indicator
Power Battery Terminal (PBT) for easy relay output connection
Four mounting holes of 3.2 mm each
PCB dimensions 51 mm x 50 mm
DO IT YOUR SELF KIT (DIY)
Kit contains components, PCB and Circuit Diagram