This part is a kind of semiconductor called RHT03.
Function of this product has Digital relative humidity & temperature sensor.
Manufacturers : MaxDetect
Image and pinout :
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Your specialist in innovating humidity & temperature sensors Digital relative humidity & temperature sensor RHT03 1. Feature & Application: *High precision *Capacitive type *Full range temperature compensated *Relative humidity and temperature measurement *Calibrated digital signal *Outstanding long-term stability *Extra components not needed *Long transmission distance, up to 100 meters *Low power consumption *4 pins packaged and fully interchangeable 2. Description: RHT03 output calibrated digital signal. It applys exclusive digital-signal-collecting-technique and humidity sensing technology, assuring its reliability and stability. Its sensing elements is connected with 8-bit single-chip computer. Every sensor of this model is temperature compensated and calibrated in accurate calibr [ ... ]