HC-05 Bluetooth Serial Wireless Module
HC-05 Bluetooth Serial Wireless Module
Product Overview
The HC-05 Bluetooth Module is a popular wireless serial communication module designed for Arduino, ESP32, Raspberry Pi, STM32, and other microcontroller projects. It enables reliable Bluetooth communication for robotics, IoT devices, home automation, and wireless control applications.
Description
The HC-05 Bluetooth Serial Wireless Module is one of the most widely used Bluetooth communication modules for embedded systems and microcontroller projects. It provides a simple and cost-effective solution for adding wireless serial communication capabilities to Arduino, ESP32, STM32, Raspberry Pi, and other development platforms.
The module supports Bluetooth SPP (Serial Port Profile), allowing seamless wireless data exchange between microcontrollers, smartphones, tablets, laptops, and Bluetooth-enabled devices.
With support for both Master and Slave operating modes, the HC-05 offers flexibility for a wide range of applications including robotics control, wireless sensor networks, home automation systems, industrial monitoring, and IoT projects.
The onboard voltage regulation circuitry allows operation from common development board power supplies while maintaining stable Bluetooth communication up to approximately 10 meters under normal conditions.
The module can also be configured using AT commands, enabling users to customize parameters such as device name, baud rate, password, and operating mode.
Applications
- Arduino projects
- ESP32 wireless communication
- Raspberry Pi Bluetooth projects
- Robotics control systems
- Home automation
- IoT devices
- Wireless sensor networks
- Bluetooth-controlled robots
- Smartphone-controlled electronics
- Industrial monitoring systems
- Data logging projects
- Embedded systems development
Key Features
- Bluetooth Serial Port Profile (SPP) communication
- Supports Master and Slave modes
- Easy UART interface integration
- Compatible with Arduino, ESP32, STM32, and Raspberry Pi
- Wireless communication up to 10 meters
- Configurable through AT commands
- Low power consumption
- Onboard voltage regulation
- Compact design
- Reliable Bluetooth connectivity
Technical Specifications
| Specification | Details |
|---|---|
| Model | HC-05 |
| Communication Type | Bluetooth Serial Communication |
| Bluetooth Version | Bluetooth 2.0 + EDR |
| Operating Voltage | 3.6V – 6V DC |
| Logic Level | 3.3V UART |
| Communication Interface | UART (TX/RX) |
| Default Baud Rate | 9600 bps |
| AT Mode Baud Rate | 38400 bps |
| Default Device Name | HC-05 |
| Default PIN Code | 1234 |
| Operating Modes | Master / Slave |
| Wireless Range | Up to 10 meters |
| Antenna Type | PCB Antenna |
Package Includes
- 1 × HC-05 Bluetooth Serial Wireless Module
Datasheet Summary
| Parameter | Value |
|---|---|
| Supply Voltage | 3.6V – 6V |
| Logic Voltage | 3.3V |
| Interface | UART |
| Default Baud Rate | 9600 bps |
| AT Command Baud Rate | 38400 bps |
| Bluetooth Protocol | SPP |
| Wireless Range | Up to 10m |
| Modes | Master / Slave |
| Supported Platforms | Arduino, ESP32, STM32, Raspberry Pi |
Pin Configuration
| Pin | Function |
|---|---|
| STATE | Connection Status Indicator |
| RXD | Serial Data Receive |
| TXD | Serial Data Transmit |
| GND | Ground |
| VCC | Power Supply |
| EN / KEY | AT Command Mode Enable |
How It Works
The HC-05 communicates using Bluetooth wireless technology and a UART serial interface. When connected to a microcontroller such as Arduino or ESP32, the module can send and receive data wirelessly between the controller and a smartphone, tablet, computer, or another Bluetooth device.
The microcontroller transmits serial data to the HC-05 through its TX and RX pins. The module converts this data into Bluetooth signals and sends it wirelessly to the paired device. Likewise, incoming Bluetooth data is converted back into serial data for the microcontroller.
For advanced configuration, the module supports AT Commands, allowing users to change settings such as the Bluetooth name, baud rate, password, and operating mode.