Digital humidity and temperature sensor-DHT11 AOSONG
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Your specialist in innovating humidity & temperature sensors Digital relative humidity & temperature sensor DHT11 1. Feature & Application: *Good precision *Outstanding long-term stability *Resistive type *Extra components not needed *Full range temperature compensated *Long transmission distance, up to 100 meters *Relative humidity and temperature measurement *Low power consumption *Calibrated digital signal *4 pins packaged and fully interchangeable 2. Description: DHT11 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 calibration chamber and the calibration-coefficient is saved in type of programme in OTP memory, when the sensor is detecting, it will cite coefficient from memory. Small size & low consumption & long transmission distance(100m) enable DHT11 to be suited in all kinds of harsh application occasions. Single-row packaged with four pins, making the connection very convenient. 3. Technical Specification: Model DHT11 Power supply 3.3-5.5V DC Output signal digital signal via Aosong 1-wire bus Sensing element Polymer humidity resistor Operating range humidity 20-90%RH; temperature 0~50Celsius Accuracy humidity +-5%RH; temperature +-2Celsius Resolution or sensitivity Repeatability Humidity hysteresis Long-term Stability Interchangeability humidity 1%RH; humidity +-2%RH; +-1%RH +-1%RH/year fully interchangeable http://www.aosong.com Thomas Liu (Sales Manager) Email: thomasliu198518@aliyun.com , sales@aosong.com

Your specialist in innovating humidity A temperature sensors 5. Electrical connection diagram: Front view Back view Side elevation Power's voltage should be 3.3-5.5V DC. When power is supplied to sensor, don't send any instruction to the sensor within one second to pass unstable status. One capacitor valued lOOnF can be added between VDD and GND for wave filtering. Aosong 1-wire bus is used for communication between MCU and DHT11. ( Aosong 1-wire bus is specially designed by Aosong Electronics Co., Ltd. , it's different from Maxim/Dallas 1-wire bus, so it's incompatible with DATA=16 bits RH...

Your specialist in innovating humidity & temperature sensors when data collecting finished if it don't receive start signal from MCU again. See below figure for overall communication process, the interval of whole process must beyond 2 seconds. -----------------------------------------------------------------------------------------------------------------------------------1) Step 1: MCU send out start signal to DHT11 and DHT11 send response signal to MCU Data-bus's free status is high voltage level. When communication between MCU and DHT11 begins, MCU will pull low data-bus and this...

_Your specialist in innovating humidity A temperature sensors Sensor outputs 1 bit data of" o Start transmit 1 bit data Start transmit next 1 bit data Host's signal Sensor's signal Sensor outputs 1 bit data of" 1 " Start transmit 1 bit data Start transmit next 1 bit data Host's signal Sensor's signal If signal from DHT11 is always high-voltage-level, it means DHT11 is not working properly, please check the electrical connection status. 8. Error and sources of error: Measure values maybe influenced by follow factors: Humidity errors Equilibration time too short, steam, water sprays, dripping...

Your specialist in innovating humidity & temperature sensors 9. Attentions of application: (1) Operating and storage conditions We don't recommend the applying RH-range beyond the range stated in this specification. The DHT11 sensor can recover after working in abnormal operating condition to calibrated status, but will accelerate sensors' aging. (2) Attentions to chemical materials Vapor from chemical materials may interfere DHT11's sensitive-elements and debase DHT11's sensitivity. (3) Disposal when (1) & (2) happens Step one: Keep the DHT11 sensor at condition of Temperature...

Your specialist in innovating humidity & temperature sensors shall pay for the return of the product to customer if the shipment is to a location within the country in which the Aosong service center is located. Customer shall be responsible for paying all shipping charges, duties, taxes, and any other charges for products returned to any other locations. This warranty shall not apply to any defect, failure or damage caused by improper use or improper or inadequate maintenance and care. Aosong shall not be obligated to furnish service under this warranty a) to repair damage resulting from...