HC-05 Bluetooth Transceiver Module – Master/Slave 6-Pin
HC-05 Bluetooth Transceiver Module – Master/Slave 6-Pin
HC-05 RF Wireless Bluetooth Transceiver Module (JY-MCU, 6-Pin)
The HC-05 Bluetooth Serial Pass-Through Module is a versatile, dual-mode wireless transceiver board designed for makers, engineers, and electronics enthusiasts. Whether you're building a DIY robotics project, a GPS navigation system, or a smart meter reading setup, this compact module delivers reliable Bluetooth V2.0 serial communication between microcontrollers, PCs, PDAs, and smartphones — right out of the box.
Key Features
- Dual Master/Slave Mode: Configurable as either a Bluetooth master or slave module, giving you maximum flexibility for your project.
- CSR Mainstream Bluetooth Chip: Uses the industry-standard CSR chipset with Bluetooth V2.0 protocol for stable, proven wireless connectivity.
- Wide Input Voltage Range: Accepts 3.3 V to 6 V input — compatible with Arduino, Raspberry Pi, and most common microcontroller platforms. Do not exceed 7 V.
- Onboard 3.3 V Regulation: Features a 150 mA / 3.3 V onboard regulator chip for clean, stable power delivery.
- Default Baud Rate 9600: Pre-configured at 9600 baud and fully user-adjustable via AT commands.
- LED Status Indicator: Built-in LED shows connection status at a glance — pulsing when unconnected, steady high when paired and communicating.
- Re-Search Button: Onboard button (and MCU-controllable high-level input) lets you trigger a fresh device scan without reprogramming.
- Anti-Reverse Protection Design: 6-pin JY-MCU backboard layout helps prevent incorrect power connections.
- Standard Pin Breakout: Exposes VCC, GND, TXD, RXD, STATE, and EN/KEY pins for easy wiring and integration.
- Compact Form Factor: Core module: 28 mm × 15 mm × 2.35 mm | Board size: 15.5 mm × 39.8 mm
Technical Specifications
| Specification | Value |
|---|---|
| Bluetooth Version | V2.0 |
| Operating Voltage | 3.3 V – 6 V (max 7 V) |
| Working Current (Pairing) | ~30 mA |
| Working Current (Connected) | ~8 mA |
| Default Baud Rate | 9600 bps (adjustable) |
| Core Module Size | 28 mm × 15 mm × 2.35 mm |
| Board Size | 15.5 mm × 39.8 mm |
| Chipset | CSR |
| Mode | Master / Slave (configurable) |
| Country of Origin | Made in China |
Compatible Applications
- Arduino, Raspberry Pi & microcontroller projects
- GPS navigation systems
- Water, electricity & gas meter reading systems
- Wireless serial data communication
- PC, laptop, PDA & smartphone Bluetooth pairing
- Robotics & automation
Important Notes
- Input voltage must not exceed 7 V — damage may result.
- This board does not have automatic reverse-polarity protection — always connect power correctly.
- The board alone has no Bluetooth functionality; a compatible Bluetooth module must be installed.
- Default configuration is slave mode; master mode requires AT command configuration.
What's in the Box
- 1 × HC-05 Bluetooth Module with JY-MCU Backboard
Learn more: ENERGY STAR product efficiency guidance
Frequently Asked Questions
Q: What is the difference between master and slave mode on the HC-05 Bluetooth module?
A: In slave mode (the default setting), the HC-05 waits for another Bluetooth device — such as a smartphone, PC, or another master Bluetooth module — to initiate the connection. In master mode, the module actively scans for and connects to nearby slave devices. You can switch between modes using AT commands via the serial interface. This makes the HC-05 one of the most flexible Bluetooth serial modules available for DIY and professional electronics projects.
Q: Is the HC-05 module compatible with Arduino?
A: Yes, the HC-05 Bluetooth transceiver module is fully compatible with Arduino boards and most other 3.3 V – 5 V microcontroller platforms, including Raspberry Pi (with a level shifter). Simply connect VCC, GND, TXD, and RXD to your board's corresponding pins and configure the baud rate to match your project's serial settings (default is 9600 bps).
Q: Can two HC-05 modules communicate directly with each other?
A: Yes — when one HC-05 is set to master mode and the other is set to slave mode, the two modules can pair and communicate seamlessly. Note that two slave modules or two master modules cannot pair directly with each other. One must be configured as master and the other as slave for a successful connection.
Q: What voltage should I use to power the HC-05 module?
A: The HC-05 accepts an input voltage between 3.3 V and 6 V. The onboard 3.3 V / 150 mA regulator handles power conversion internally. Never exceed 7 V, as this can permanently damage the module. Always double-check your power supply polarity before connecting, as the board does not include automatic reverse-polarity protection.
Production & Packaging Notice
To maintain high stock availability and fast shipping times, our items are sourced from multiple verified manufacturing facilities. While the core quality, materials, and product specifications remain identical, you may notice slight variations in the packaging design, manufacturing origin, or the wording of the printed instructions.