Flame sensor with 3-pin digital output

The Speed of Light Detection Standard thermal sensors (like thermistors) require ambient heat to rise before they trigger, which can take critical minutes during a fire. This IR Flame Sensor works completely differently. The large, black LED-like component protruding from the front is an infrared photodiode. Flames naturally emit a massive amount of infrared radiation in the 760nm to 1100nm wavelength range. The dark epoxy casing of the photodiode acts as a filter, blocking out visible daylight while allowing these specific fire-indicating IR wavelengths to pass through. This means the sensor detects a flame the exact millisecond it ignites.

LM393 Precision & Adjustable Sensitivity Reading raw, fluctuating analog data from a photodiode can be tricky. This breakout board handles the hard work for you by incorporating an LM393 voltage comparator chip. It takes the raw signal and translates it into a sharp, definitive digital High or Low. Even better, you can dictate exactly when that trigger happens by turning the crosshead screw on the blue potentiometer. Turn it one way, and it will only trigger for a massive bonfire. Turn it the other, and it can detect the tiny flame of a lighter from almost a meter away!

Simple 3-Pin Integration. This module is strictly a digital sensor, making it incredibly easy to use. It features three pins: VCC, GND, and DO (Digital Out). Simply power it with 3.3V or 5V, connect the DO pin to any digital pin on your Arduino, and use a basic digitalRead() command in your code. The board also features two onboard surface-mount LEDs: a Power LED to confirm the board is on, and a DO-LED that lights up exactly when the trigger threshold is crossed, allowing you to calibrate the sensor without even looking at your computer screen.