AM2301 DHT21 Digital Capacitive Temperature and Humidity Sensor for Arduino Raspberry Pi Alternative to SHT10 SHT11

Description

AM2301 DHT21 Digital Temperature and Humidity Capacitive Sensor Arduino Raspberry alternative to SHT10 SHT11

1). Relative humidity and temperature measurement, calibration, all digital output
2.) excellent long-term stability
3). No additional components
4). Long-distance signal transmission
5) low power consumption
6). 4-pin installation
7.) fully interchangeable
AM2301 product description:
AM2301 digital temperature and humidity sensor contains a composite temperature and humidity sensor with calibrated digital signal output. Dedicated digital module acquisition technology and temperature and humidity sensor technology ensure that the product has very high reliability and excellent long-term stability.
The sensor includes a capacitive humidity element and a DS18B20 temperature measurement device, and is connected to a high-performance 8-bit microcontroller. Therefore, the product has excellent quality, super-fast response, strong anti-jamming capability, and performance advantages at very high costs.
Each calibration of the AM2301 sensor in the humidity calibration laboratory is extremely precise. Calibration coefficient in the form of a program stored in OTP memory, inside the sensor during the signal processing detection process to recall this calibration coefficient. Single-wire serial interface, system integration becomes simple and fast. Extremely reduced volume, low power consumption, signal transmission distance of 20 meters, making it an optimal choice even for the most demanding applications, product lead for the three-wire shielded cable.
Areas of application:
1) hvac 2) test and inspection equipment
3) automatic recorder 4)
5) 6) consumer goods control
7) weather station 8) appliances
9) humidity regulator 10) medical assistance
parameters:
Measurement range of the model’s resolution of the temperature measurement accuracy of the humidity measurement, measurement accuracy of the temperature
AM2301 0-100% RH – 40 ~ 80 C at +/- 3% RH + 0.5 0.1 C
Compatibility can be fully interchangeable
Long-term stability of +/- 0.3% RH / year
Power supply pins:
The AM2301 power supply voltage ranges from 3.3 to 6 V. After the sensor is powered on, wait 1 s to pass through the unstable state, during this period no instruction needs to be sent. The power pins (VDD and GND) can increase the capacitance of 100 nf for decoupling and filtering.
Single bus interface:
Single bus data for communication between microprocessor and AM2301 and synchronization, a communication time of approximately 5 ms, specific format as shown below, 40-bit current data, high on the first output.
Data format: 40-bit data = 16 + 16 bit temperature data bits + 8-bit checksum
Example: 40-bit data received are as follows:
0000 0010 1000 1100 0000 0001 0101 1111 1110 0001
Humidity, validation of temperature and data
Checksum = (low humidity high 8 + 8 + 8 + high temperature low temperature 8) sum of 8, for example: at the end of checksum = 0000 + 0010 + 1000 1000 0010 0001 0001 + 0101 = 1110, 1110
This humidity case = 65.2% RH, calculation method for humidity value: insert humidity data from binary to obtain 652 0000 0010 1000 0000 is converted into decimal, humidity = 652/10 = 65.2% relative humidity. The calculation method for temperature and humidity values is the same, so in this case = 35.1 C of temperature.
When the temperature is below 0 C, the temperature data of the highest position 1.
For example: 10.1 C for 1000, 0000, 0110, 0101
User guest (MCU) to send a start signal, AM2301 from low power mode to high speed mode, after waiting for the host signal start, AM2301 to send the response signal, sending 40 bits of data and start signal acquisition.
(note: the host for reading AM2301 temperature and humidity data always stores the latest measurement, for example, if the measurement intervals are very long, please read twice consecutively for real-time temperature and humidity)

Product Overview AM2301 / DHT21
a digital temperature and humidity sensor AM2301 / DHT21 with a calibrated digital signal output of the combined temperature and humidity sensor. The digital acquisition technology of the module is specifically designed for temperature and humidity sensing applications to ensure products with high reliability and excellent long-term stability. The sensor includes a capacitive humidity sensing element and an NTC temperature measurement device, connected to a high-performance 8-bit microcontroller. The product has excellent quality, fast response, anti-interference capability, cost-effectiveness, and other advantages. Each AM2301 / DHT21 sensor has an extremely precise humidity calibration chamber for calibration. Calibration coefficients are stored as a program in OTP memory, and the sensor’s internal signal detection processing calls these calibration coefficients. The single-wire serial interface makes system integration simpler and faster. The ultra-small size, low power consumption, and signal transmission distance up to 20 meters make it the best choice for a variety of applications, including the most demanding ones. The product comes in a single-row 4-pin pin package. Practical connection, special packages can be provided based on user requirements.

applications
HVAC test and test equipment
Automotive data loggers
Automatic consumer goods control
Weather station devices
Medical humidistat
Dehumidifier

Tutorial: How to use the AM2301 DHT21 Sensor

The AM2301 sensor measures temperature and humidity. Perfect for environmental monitoring projects.

What you need

• Arduino
• AM2301
• USB cable

Steps

1. Connect VCC to 5V on Arduino.
2. Connect GND to ground on Arduino.
3. Connect DATA to digital pin 2 on Arduino.
4. Check connections and connect the sensor to the network via USB.
5. Install the DHT sensor library on Arduino IDE.
6. Include the library in your sketch: #include
7. Create a DHT object: DHT dht(D2, DHT11);
8. Read temperature and humidity with dht.readTemperature() and dht.readHumidity().

Example code

void setup() {
  Serial.begin(9600);
}

void loop() {
  float temp = dht.readTemperature();
  float humi = dht.readHumidity();
  Serial.print(temp); Serial.print(" "); Serial.println(humi);
}

Mini project

Create an alarm system for extreme temperature or humidity conditions.

Common mistakes

• Incorrect VCC/GND connection
• Incorrect DATA pin
• DHT library not installed

Recommended accessories

• LCD 16×2 Display
• Relay Module
• Buzzer

Frequently asked questions

How can I check if the sensor is working?
Check the temperature and humidity in a stable environment. If the values are consistent, the sensor should be working.

What other sensors can replace the AM2301?
SHT10 or SHT11