# Bluetooth module HC-05, compatible

- Page: https://sigmanortec.ro/en/bluetooth-module-hc-05-compatible
- Price: 27.04 RON
- Availability: In stock; 1-2 zile
- Reference: 33274 · EAN: 5941662681976
- Category: Mechatronics and IoT > Sensors and Modules > Bluetooth Modules
- Package (shipping data): 0.003 kg
- Updated: 2026-09-14
- Shop: [Sigmanortec.ro](https://sigmanortec.ro/en/llms.txt)
- Prices: RON, VAT included; prices and stock as of 2026-10-22 03:25 (Europe/Bucharest)

## Description

Bluetooth module for wireless serial communication between Arduino or other boards and phone or PC, works as Master or Slave, fast connection via UART TTL with default setting 9600 bps, supports Data Mode and AT Command Mode for configurations such as name, password and baud rate, 3.6-6V power supply and low consumption, ideal for automation and remote control projects.
The HC-05 Bluetooth module, compatible with Arduino and other development boards. This module is used together with development boards for serial communication via Bluetooth. It can be used both as Master and as Slave.
This version uses the integrated HC-05 compatible chip, a cheaper but reliable version.
With two modules, wireless communication can be established between two microcontrollers such as Arduino or between a microcontroller and a Bluetooth device such as a phone or a computer.
Communication is done via USART at a baud rate of 9600. The data transfer capacity does not extend to music files or photos.
Important: The Arduino RX pin works with both 5V and 3.3V. The RX pin on the HC-05 module does NOT tolerate 5V logic level. Use a level converter or a voltage divider with 1k and 2k resistors. Resistors with higher values will prevent fast data transmission.
* In the example above, a voltage divider made of 2 resistors is used to protect the RX pin
The module operates in two modes:
Data mode: can receive and send data between Bluetooth devices
AT Command mode: in this mode you can change the module settings such as Baud Rate, Name, Password, etc.
Specifications:
Supply voltage: 3.6 - 6V
RX pin logic voltage: 3.3VDC
Operating current: 30mA
Communication: Serial USART and TTL compatible
IEEE 802.15.1
FHSS
Bluetooth name: HC-05
Default password: 1234 or 0000
Default mode: Data Mode
Data Mode Baud Rate: 9600, 8, N, 1
Command Mode Baud Rate: 38400, 8, N, 1
Default firmware: LINVOR
Supported baud rates: 9600, 19200, 38400, 57600, 115200, 230400, 460800
Pins:
Enable/Key: Used to switch between Command Mode and Data Mode
VCC: 5V power supply
GND: Ground
TX: Pin that transmits serial data. Connect this to the RX pin on the Microcontroller
RX: Pin that receives serial data. Connect this to the TX pin on the Microcontroller
State: Pin connected to the integrated LED to display the module's status
Using the Key pin:
Together with Arduino, the module can also be connected to other digital pins using SoftwareSerial. When connecting the module directly to the RX and TX pins of the development board, these pins must be disconnected before uploading code to the board, otherwise the Arduino IDE will return an upload error.
Useful links:
AT Command List: Click here