HC-05 6pin Bluetooth Module with Button

HC-05 6-Pin Bluetooth Module with Button delivers a reliable, cost-effective solution for adding wireless serial communication to embedded systems, microcontrollers, and electronic projects. This popular module utilizes the Serial Port Profile (SPP), effectively replacing bulky UART cables with a transparent, full-duplex Bluetooth link. The 6-pin breakout board includes an integrated voltage regulator, allowing you to easily connect the module to common 5V systems without external level shifting. Furthermore, the key feature of this specific version is the on-board push button, which simplifies the process of entering the powerful AT Command mode for configuration. Consequently, this module enables rapid prototyping and deployment in Master or Slave roles, making wireless data exchange simple and efficient.

Key Features:

• Dual Operating Modes: You can configure the HC-05 to operate as either a Master (initiates connection) or a Slave (accepts connection), providing flexibility for diverse network topologies.
• Integrated AT Mode Button: The on-board switch simplifies access to the AT command set, therefore allowing users to quickly change parameters like Baud Rate, device name, and pairing password.
• Bluetooth V2.0+EDR: This module supports Enhanced Data Rate (EDR) for robust and faster data transmission up to 3 Mbps (theoretical), using the standardized IEEE 802.15.1 protocol.
• Wide Voltage Compatibility: An integrated 3.3V regulator allows the module to safely accept a 5V supply (V_CC), providing compatibility with Arduino and most 5V microcontrollers.
• Full-Duplex Serial Communication: The transparent serial link allows simultaneous sending (TX) and receiving (RX) of data once the connection is established.

Technical Specifications:

• Bluetooth Protocol: Bluetooth V2.0 + EDR
• Frequency Band: 2.4 GHz ISM band
• Operating Voltage: 4 V to 6 V DC (On-board 3.3V regulator)
• Logic Level Voltage: 3.3 V (I/O pins are often 5V tolerant on breakout boards)
• Communication Range: Typically ≈ 10 meters (33 ft) in open space
• Default Data Baud Rate: 9600 bps
• Default AT Command Baud Rate: 38400 bps
• Sensitivity: Typical −80 dBm
• Modulation Method: GFSK (Gaussian Frequency Shift Keying)

Mechanical Specifications:

• Module Chipset: CSR BlueCore 04-External
• Package Style: PCB Adapter Board with Integrated Antenna
• Connection Type: 6-Pin Header (Male or Female, depending on supplier)
• Status Indicator: On-board LED (Indicates pairing status and connection)

Dimensions:

• Overall Module Dimensions (L × W): ≈ 37 mm × 16 mm
• Component Board Footprint: ≈ 27 mm × 13 mm
• Pin Pitch: 2.54 mm (Standard header spacing)
• Weight: ≈ 3 g (Extremely light for portable applications)

Pinout and Wiring:

• KEY/EN: Controls the mode. Pull high (V_CC) to enter AT Command mode upon power-up; leave low or floating for Data mode.
• VCC: Connect the module to a stable +5 V or +3.3 V DC power supply.
• GND: Connect to the circuit ground (0 V).
• TXD (Transmit): Transmits serial data out; connect to the microcontroller’s RXD pin.
• RXD (Receive): Receives serial data in; connect to the microcontroller’s TXD pin. (Note: Use a level shifter or voltage divider if the MCU’s TX is 5V and the module’s RX is strictly 3.3V.)
• STATE: An output pin that signals connection status (e.g., typically blinks when searching, stays high when connected).

Datasheet Reference:

• Download HC-05 Bluetooth Module Datasheet

Commonly Used in:

• Arduino and Microcontroller Projects: Engineers use the module extensively to add wireless capability to platforms like Arduino, ESP32, and PIC microcontrollers.
• Robotics: You will find the HC-05 commonly used for wireless control and debugging of mobile robots.
• Data Logging Systems: It allows systems to send collected sensor data wirelessly to a PC or smartphone for monitoring and recording.

Applications:

• Remote Control Systems: Implement simple wireless control for home automation devices, toys, and custom gadgets using a mobile app.
• Wireless Serial Bridge: Creates a transparent bridge between two microcontrollers or between a computer’s serial port and an embedded device.
• Diagnostic Tools: Conversely, developers use it for wireless debugging, allowing a remote terminal connection to view system status without a physical cable.

Equivalent Models:

• HC-06: A simpler, lower-cost alternative that however only operates in Slave mode (cannot initiate a connection).
• HC-04 / HC-03: Older versions that perform the same core function but often feature different AT command sets or physical footprints.
• JY-MCU (HC-05 Variant): This is a common manufacturer name for the HC-05 module, indicating functional equivalence.

Package Includes:

• 1 x HC-05 6-Pin Bluetooth Module (Master/Slave Configurable)