MW33 Digital Temperature and Humidity Sensor Module
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Overview
About MW33 Digital Temperature and Humidity Sensor Module
The MW33 is a digital sensor module designed for ambient temperature and humidity measurement. It integrates a DHT11 sensor, which uses a capacitive humidity sensor and a thermistor to provide accurate readings.
⚡ Key Features
- DHT11-Based Sensor – Reliable temperature and humidity measurements.
- Single-Wire Communication – Easy integration with ESP32, Arduino, and other microcontrollers.
- Compact & Efficient – Ideal for HVAC systems, environmental monitoring, and IoT projects.
With its simplicity and reliability, the MW33 is a great choice for basic climate monitoring applications. 🚀
Get Your MW33
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$3 per unit
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MW33 Specifications
Complete technical specification details for MW33 Digital Temperature and Humidity Sensor Module
📊 Technical Parameters
MW33 Pinout
The MW33 is a DHT11-based sensor module with 3 pins: VCC, DATA, and GND for single-wire communication.
Visual Pinout Diagram
Pin Types
Quick Tips
on DHT11 sensor (capacitive humidity + thermistor),[object Object]
Object],Single-wire communication protocol
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Pin Descriptions
| Pin Name | Type | Description | Notes |
|---|---|---|---|
1 VCC | Power | Power supply input (3.3V or 5V). Powers the DHT11 sensor. | Both 3.3V and 5V compatible. |
2 DATA | Digital | Single-wire digital output. Transmits temperature and humidity data. | Requires 10kΩ pull-up resistor to VCC. |
3 GND | Power | Ground connection. Connect to microcontroller ground. |
Wiring MW33 to ESP32
To interface the MW33 with an ESP32, connect VCC to 3.3V or 5V, GND to ground, and DATA to a GPIO pin with a 10kΩ pull-up resistor.
Pin Connections
| MW33 Pin | Connection | ESP32 Pin | Description |
|---|---|---|---|
1 VCC Required | 3.3V or 5V | Power supply. Use 3.3V or 5V depending on preference. | |
2 GND Required | GND | Ground connection. | |
3 DATA Required | GPIO 4 | Single-wire data line. Requires 10kΩ pull-up resistor to VCC. |
Object]
DHT11 or DHT library for reading data
Object]
reading after power-on may be unreliable - discard it
sensor away from heat sources for accurate readings
direct sunlight and rapid temperature changes
to DHT11 - use same libraries and code examples
MW33 Troubleshooting
Common issues and solutions to help you get your sensor working
Common Issues
Issue: The MW33 sensor is not recognized by the microcontroller, resulting in failed data readings.
Possible causes include incorrect wiring, insufficient power supply, or a faulty sensor.
Solution: Verify that the sensor's VCC is connected to a 3.3V-5V power source, GND to ground, and the data output (DO) to the appropriate digital input pin on the microcontroller. Ensure that the connections are secure and that the sensor is receiving adequate power. If the problem persists, consider testing the sensor with a different microcontroller or replacing the sensor.
Issue: The MW33 sensor provides temperature or humidity readings that are inconsistent or outside the expected range.
Possible causes include environmental interference, sensor placement, or sensor malfunction.
Solution: Ensure that the sensor is placed in an environment within its operating temperature range of 0°C to 50°C and humidity range of 20% to 95%. Avoid placing the sensor near heat sources, direct sunlight, or areas with rapid temperature changes. If inaccuracies persist, consider calibrating the sensor or replacing it if it is found to be defective.
Issue: The sensor outputs fluctuating temperature or humidity values, leading to unreliable data.
Possible causes include unstable power supply, loose connections, or environmental factors.
Solution: Ensure that the sensor is connected to a stable power source within the specified voltage range (3.3V-5V). Check all wiring connections for stability and secure any loose connections. Consider placing the sensor in an environment with stable temperature and humidity levels to minimize fluctuations.
Issue: The MW33 sensor exhibits slow response times to changes in temperature or humidity.
Possible causes include sensor limitations or environmental conditions.
Solution: Recognize that the MW33 sensor may have inherent response time limitations. Ensure that the sensor is exposed to the environment without obstructions that could impede airflow. If faster response times are critical, consider using a sensor with a quicker response specification.
Debugging Tips
Use the Serial Monitor to check for error messages and verify the sensor's output. Add debug prints in your code to track the sensor's state.
Use a multimeter to verify voltage levels and check for continuity in your connections. Ensure the power supply is stable and within the sensor's requirements.
Additional Resources
MW33 Programming Examples
Ready-to-use code examples for different platforms and frameworks
#include "DHT.h"
#define DHTPIN 4 // Digital pin connected to the DHT sensor
#define DHTTYPE DHT11 // DHT 11
DHT dht(DHTPIN, DHTTYPE);
void setup() {
Serial.begin(115200);
Serial.println("MW33 Sensor Example");
dht.begin();
}
void loop() {
// Wait a few seconds between measurements
delay(2000);
// Reading temperature or humidity takes about 250 milliseconds!
float humidity = dht.readHumidity();
// Read temperature as Celsius (the default)
float temperature = dht.readTemperature();
// Check if any reads failed and exit early (to try again).
if (isnan(humidity) || isnan(temperature)) {
Serial.println("Failed to read from DHT sensor!");
return;
}
Serial.print("Humidity: ");
Serial.print(humidity);
Serial.print(" % ");
Serial.print("Temperature: ");
Serial.print(temperature);
Serial.println(" °C");
}#include <stdio.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "driver/gpio.h"
#include "dht.h"
#define DHT_PIN GPIO_NUM_4
void app_main() {
setDHTgpio(DHT_PIN);
while (1) {
printf("Reading MW33 sensor...\n");
int ret = readDHT();
errorHandler(ret);
printf("Humidity: %.1f%%\n", getHumidity());
printf("Temperature: %.1f°C\n", getTemperature());
vTaskDelay(2000 / portTICK_PERIOD_MS);
}
}sensor:
- platform: dht
pin: GPIO4
model: DHT11
temperature:
name: "Living Room Temperature"
humidity:
name: "Living Room Humidity"
update_interval: 60splatformio.ini
[env:esp32dev]
platform = espressif32
board = esp32dev
framework = arduino
lib_deps =
adafruit/DHT sensor library @ ^1.4.4
monitor_speed = 115200main.cpp
#include "DHT.h"
#define DHTPIN 4 // Digital pin connected to the DHT sensor
#define DHTTYPE DHT11 // DHT 11
DHT dht(DHTPIN, DHTTYPE);
void setup() {
Serial.begin(115200);
Serial.println("MW33 Sensor Example");
dht.begin();
}
void loop() {
delay(2000); // Wait 2 seconds between measurements
float humidity = dht.readHumidity();
float temperature = dht.readTemperature();
if (isnan(humidity) || isnan(temperature)) {
Serial.println("Failed to read from MW33 sensor!");
return;
}
Serial.print("Humidity: ");
Serial.print(humidity);
Serial.print(" % ");
Serial.print("Temperature: ");
Serial.print(temperature);
Serial.println(" °C");
}from machine import Pin
from time import sleep
import dht
# Initialize the DHT sensor
sensor = dht.DHT11(Pin(4))
print("MW33 Sensor Example")
while True:
try:
sensor.measure()
temperature = sensor.temperature()
humidity = sensor.humidity()
print("Temperature: {:.1f}°C".format(temperature))
print("Humidity: {:.1f}%".format(humidity))
except Exception as e:
print("Error reading from MW33 sensor:", e)
sleep(2)Wrapping Up MW33
The ESP32 MW33 Digital Temperature and Humidity Sensor Module is a powerful environment sensor that offers excellent performance and reliability. With support for multiple development platforms including Arduino, ESP-IDF, ESPHome, PlatformIO, and MicroPython, it's a versatile choice for your IoT projects.
Best Practices
For optimal performance, ensure proper wiring and follow the recommended configuration for your chosen development platform.
Safety First
Always verify power supply requirements and pin connections before powering up your project to avoid potential damage.
Ready to Start Building?
Now that you have all the information you need, it's time to integrate the MW33 into your ESP32 project and bring your ideas to life!
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