3.3-5V Rain Raindrops Detection Sensor Weather Humidity Module For Arduino Brand New Feature: 1.The sensor USES the high quality FR - 04 double material, large area of 5.5 * 4.0CM, treatment of nickel plating and surface, have fight oxidation, electrical conductivity, and life has more superior performance; 2.With potentiometer sensitivity adjustment; 3.The output format: digital switch output (0 and 1) and analog AO voltage output; 4.Has a fixed bolt hole, convenient installation; 5.The comparator output, signal clean, good waveform, driving ability is strong, for more than 15 mA; 6.The LM393, use of wide voltage comparator; 7.The working voltage of 3.3 V to 5 V; Size: Like the picture show   Usage: - Connected to 5 v power supply power lights, no water droplets on induction plate, the DO output for the high level, switch lights out, a drop of water drops, the DO output for the low level, switch indicator,brush away the water droplets, return to again, the output high level state. - AO analog output, can be connected to the microcontroller AD mouth drops of rainfall in the above size. - DO TTL digital output can also be connected microcontroller detecting whether it will rain.