The raindrop sensor module can be utilized for rainfall detection. It is for measuring intensity. The module involves a rain board along with a controller board which are different for additional convenience. It's a power indicator LED and a flexible sensitivity even though a potentiometer. The module relies on the LM393 op amp. As rain drops are accumulated on the circuit board they produce avenues of parallel resistance which are quantified through the op amp. The lower the resistance (or even the more water), the lower the voltage output.Conversely, the water, the larger the output voltage over the analog pin. An entirely dry board such as will get the module to output volts.