I am trying to adjust the sensitivity of a KY-038 sensor. I have connected the digital output to pin D4 and the analog to A0, and adjusting I have realized that if I lower the value of A0 below 600 (approximately), the sensor stops working and always returns me at the digital output HIGH. I have tested with two KY-038 sensors and the same happens in both, what do you think the problem may be?
A greeting and thanks in advance