LM393 Photosensitive Light-Dependent Control Sensor LDR Module is used to detect the intensity of light. When there is light, the resistance of LDR will become low according to the intensity of light. The greater the intensity of light, the lower the resistance of LDR. The sensor has a potentiometer knob that can be adjusted to change the sensitivity of LDR towards light. With such a wide variation in resistance, LDRs are easy to use.

Features :

LM393 based design
Can detect ambient brightness and light intensity
Adjustable sensitivity (via blue digital potentiometer adjustment)
Output Digital – 0V to 5V, Adjustable trigger level from preset
Output Analog – 0V to 5V based on light falling on the LDR
LEDs indicating output and power

Specification:

Operating Voltage(VDC)	3.3 to 5
Operating Current(mA)	15
Length (mm)	32
Width (mm)	14
Height (mm)	8
Weight (gm)	3

How it works:

Light detecting resistor(LDR) module most sensitive to environmental light intensity is generally used to detect the ambient brightness and light intensity.
Module light conditions or light intensity reach the set threshold, DO port output high when the external ambient light intensity exceeds a set threshold, the module D0 output low;
Digital output D0 directly connected to the MCU, and detect high or low TTL, thereby detecting ambient light intensity changes;
Digital output module DO can directly drive the relay module, which can be composed of a photoelectric switch;
Analog output module AO and AD modules can be connected through the AD converter, you can get a more accurate light intensity value

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