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(After August 23rd 2018)



New Product

Smart Phone/LAN FAX adapter

PCIe / PCIe (M2) Wi-Fi Module

Embedded Wi-Fi to Serial module
    temperature range -40 to +105°C

Embedded Wi-Fi AP/router adapter

USB 3.0 to Gigabit LAN

Wireless Sensor (BLE or Wi-Fi)

AIO Network Hub (USB/Wi-Fi/LAN)


PSTN, Dial-Up Modems

By Interfaces -

- PCIe Wi-Fi

- PCIe (M2) Wi-Fi

- Serial TTL, Internal

- RS232, Internal, 12/24/48V

- RS232, Standalone

- USB, Internal

- USB, Standalone

- PC/104

- ISA Bus


By Applications -

- Medical Modems

- Contact ID Modems

- Leased-Line Modems

- Bell 202 Compatible

- Speakerphone Modems


Wireless Modems

Wi-Fi Modems -




Bluetooth Modems

3G Cellular Modems

2.4GHz Transceiver


LAN Products

Serial to Ethernet Modules

USB to Ethernet Adapters

LAN/Wi-Fi/USB/Serial Converter

LAN to Serial/Modem Adapter


PC/104 Products

PC/104 Modem

PC/104 3G Cellular

PC/104 Wi-Fi

PC/104 LAN


Custom Specifications

Build-to-Suit, Wired or Wireless


Bluetooth Class 1 Audio Modules – RB540, RB540HM
- A2DP / HFP / HSP Support
- Allows Flawless Data While Music Streaming
Up to 650 ft (200 Meters) Range




RB540 (SMD Module)

The RB540 series features a Class 1 Bluetooth data with simultaneous audio module for system integrators. The RB540 comes complete with DSP, stereo CODEC, flash memory and on board antenna. The module offers superior audio quality, power consumption and radio performance making it ideal for high quality Bluetooth headset designs and most stereo and mono audio applications.

The embedded DSP core is an open platform digital signal coprocessor allowing product-enhancing features such as advance audio decoding (MP3, AAC, AAC+), speech recognition, text-to-speech, echo cancellation and noise reduction.

With Class 1 radio, transmission power up to 20dBm, the RB540 series can connect to other Bluetooth devices such as MP3/MD/CD players, mobile phones, and desktop or notebook computers, PDA etc., in range up to 650 ft. (200 meters).

The RB540 series combines Bluetooth Basic Rate (BT 3.0) technology to provide increased throughput, reduced battery consumption and improved security. It also provides faster pairing and allows superior performance in the presence of interference from 802.11 Wi-Fi wireless devices and other 2.4GHz radios.

The RB540 series has on board flash memory available to upgrade the module’s firmware, modify parameters, or implement custom features. Radicom is capable to modify the firmware to meet ODM / OEM requirements and create custom Bluetooth functionality to meet OEM’s specific needs.

TrueWirelss (TWS) technology allows for streaming A2DP music on the master device which then relays the audio stream to a slave device. It also supports sending data or command to control master and slave through a smart phone or tablet.

With Radicom Research’s proprietary True Audio Data (TAD) protocol, the RB540 allows smart phones to transmit data to control devices during music streaming without affecting the audio signal. It supports audio A2DP, handset, hands-free wireless profiles.

There are two platforms available: The RB540 is a surface mount PCB module with on-board antenna. The RB540HM is a DIP, through-hole module continuing the popular Radicom “HM” footprint of 1” x 1”. The RB540HM also has an U.FL connector built in for attaching an antenna cable allowing flexibility to place antenna at a desired location.


  • Class 1 radio, transmission power up to 20dBm
  • Bluetooth V3.0, V2.1+EDR  support
  • UART / SPI interfaces (optional for special firmware)
  • Small sizes: 1.55” x 0.70” x 0.10” (RB540-a), 1.00" x 1.33" x 0.25" (RB540HM-c)
  • Weight: 0.1oz (RB540-a)
  • Serial Port Profile (SPP) support
  • A2DP, AVRCP, HFP / HSP support
  • 64MIPS Kalimba DSP co-processor
  • Up to 16Mbits flash memory on board (firmware dependent – 8Mbits typical)
  • Secure communications with 128-bit encryption (optional)
  • On-board antenna (RB540-a, RB540HM-a)
  • On-board U.FL connector for external antenna (RB540HM-c)
  • Support 802.11 wireless coexistence
  • -40°C to +85°C extended temperature operating
  • RoHS compliant
  • FCC, IC and CE (pending)
  • High Quality Stereo & Mono Headsets

  • Bluetooth Speakers

  • AV Transmitters

  • Hand-free Car Kits

  • MP3 Players

  • VoIP Headsets

  • Audio Dongles

  • Automotive Wireless Gateway

  • Cordless Phone (TX/RX)

  • Intercom

  • Long Range Locators



1.55” x 0.70”x 0.10” (RB540-a), 1.00” x 1.33” x 0.25”(RB540HM-c)

Device Type

Embedded Bluetooth OEM modules



Data Link Protocol

Bluetooth V3.0, V2.1+EDR


2.402 – 2.480 GHz

Transmit Power

20dBm max.

Nominal Sensitivity


Bluetooth Class

Class 1


Up to 200 meters

On Board Flash

8Mbits, 32Mbits (optional)


128-bit encryption (optional)

Power Consumption

Standby: <4mA, SCO Link: <43mA (under calling), A2DP Streaming: <45mA (music playing)

Supply Voltage: VDD

3.0V - 3.6V


Optional Chip On-board or U.FL connector for external antenna (HM)

Baseband Crystal OSC


RF Input Impedance

50 ohms

Receiver IF Frequency


Receiving Signal Range

-90 to –20dBm typical


1600hops/sec, 1MHz channel space

Operating Temperature

-40ºC to +85ºC

Storage Temperature

-40ºC to +125ºC


RoHS compliant

Ordering Information




Surface mount, long range Class 1 Bluetooth Audio module with PCB antenna. Typical 8Mbits FLASH.
- Range: 100 meters
- 20dBm transmission power (max.)
- SPP support


Surface mount, long range Class 1 Bluetooth Audio module. Typical 8Mbits FLASH.

RB540HM-a or -c

Dual-in-line, Dip(though-hole) Bluetooth Audio module. Typical 8Mbits FLASH with 16 Mbits FLASH optional

Model: RB540HM-a: With on-board PCB antenna
Model: RB540HM-c: External antenna

RB540EK (-a/-c)

RB540 Evaluation Kit. The RB540EK contains a RB540MB with a RB540HM(-a/-c). Each kit consists of the following components:

1. RB540HM (-a/-c) mounted on a RB540MB Main Board.
2. USB Power cable (A to B)
3. external antenna (optional for RB540HM-c)
4. antenna cable (optional for RB540HM-c)


RB540HM Replacement antenna, 2.4GHz, 2dBi, RP-SMA, Omni- directional.

antenna cable

RB540HM 6" U.FL. to RP-SMA female connector antenna cable

Mechanical Diagram & Pin Assignments - RB540-a

GND (P) 24 A19 (I) 57 GND (P)
2 RF (I/O) 25 PIO14 (I/O) 56 GND (P)
3 GND (P) 26 PIO11 (I/O) 55 SPK_L_P (O)
4 GND (P) 27 PIO5 (I/O) 54 SPK_L_N (O)
5 3V3 (I) 28 PIO6 (I/O) 53 SPK_R_N (O)
6 GND (P) 29 PCM_IN (I) 52 SPK_R_P (O)
7 PIO3 (I/O) 30 PCM_SYNC (I/O) 51 MIC_L_P (I)
8 PIO2 (I/O) 31 PCM_OUT (O) 50 MIC_L_N (I)
9 AIO1 (I/O) 32 PCM_CLK (I/O) 49 MIC_R_N (I)
10 AIO0 (I/O) 33 PIO12 (I/O) 48 MIC_R_P (I)
11 UART_CTS (I) 34 PIO7 (I/O) 47 MIC_BIAS (O)
12 UART_RTS (O)     46 LED0 (O)
13 PIO10 (I/O)     45 LED1 (O)
14 UART_TX (I)     44 nRST (I)
15 UART_RX (O)     43 GND (P)
16 PIO15 (I/O)     42 VDD_CHG (I)
17 USB_DN (I/O)     41 BAT_P (I)
18 USB_DP (I/O)     40 LX (O)
19 PIO9 (I/O)     39 IV8 (I)
20 SPI_MOSI (I)      38 GND (P)
21   SPI_CLK(I)     37 VREGEN_H (I)
22  SPI_CSB (I)     36 PIO4 (I/O)
23  SPI_MISO (O)     35 PIO8 (I/O)

I: Input
O: Output
I/O: Input/Output
P: Power

Mechanical Diagram & Pin Assignments - RB540HM-a or c

NC 28 SPK_R_P (O)
2 N/A 27 SPK_R_N (O)
3 PIO2 (I) 26 SPK_L_N (O)
4 PIO3 (I) 25 SPK_L_P (O)
6 VOL+ (I) 23 MIC (I)
7 MUTE (I) 22  LED0 (O)
8 CALL_END (I) 21  LED1 (O)
10 VOL- (I) 19  VBAT (I)
11 SPI_MOSI (I) 18  GND (P)
12 SPI_CLK (I) 17  3V3 (P)
13 SPI_CS (I) 16  PIO4 (O)
14 SPI_MISO (O) 15  PIO8 (O)

I: Input
O: Output
I/O: Input/Output
P: Power





Information furnished by Radicom Research is believed to be accurate and reliable.  However Radicom Research assumes no responsibility for its use, or any infringement of patents or other rights of third parties which may result from its use.  Radicom Research reserves the right to change circuitry at any time without notice.  This document is subject to change without notice.

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