Rain sensor, can be used for all kinds of weather monitoring, and translated into output signals and AO. The sensor USES the high quality double material, large area of 5.5 * 4.0 CM, treatment of nickel plating and surface, have fight oxidation, electrical conductivity, and life has more performance. The comparator output, signal clean, good waveform, driving ability is strong, for more than 15 mA. With potentiometer sensitivity adjustment. The working voltage of 3.3 V - 5 V The output format: digital switch output (0 and 1) and analog AO voltage output. Has a fixed bolt hole, convenient installation. Small board PCB size: approx. 3.2 x 1.4 cm Use of wide voltage LM393 comparator. Specification: Connect the 5V power supply, power indicator light, sensor board doesn't has waterdrop, DO output is high level, the switch lights off, dripping a drop of water, DO output is low level, the switch indicator lamp light up. Remove the waterdrop, it returned to the output high level. AO analog output can be connected to the microcontroller AD port and detects the amount of rainfall. DO TTL digital outputs can also be connected to the microcontroller detects whether there is rain. VCC: Power Positive Pole 3-5V GND: Power Negative pole DO: TTL switching signal output. AO: Analog output. Package Includes: 1 Piece Rain Sensor 1 Piece Rain Module 2 Pieces Cable