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Zigbee Wireless Mesh Networking
ETRX3 3rd Generation ZigBee Module
Product ID: ETRX3

The ETRX3 is the 3rd generation of advanced ZigBee modules from Telegesis and the first module family on the market to feature the EM357 the latest ARM® Cortex M-3 based SOC from Ember.

The ETRX3 has a footprint of just 19mm x 25mm for both standard and PA/LNA versions which represents a 40%reduction in size compared to the ETRX2 module and will be available with either an on board antennae or a Hirose U.FL connector to allow connection of external antennae.


  ETRX3 prototype mounted on large format carrier board

A link budget of 105dB on the standard ETRX3 module gives excellent performance and RF power can be further boosted by use of the ETRX3-LR which adds an extra LNA+PA boosting the link budget to 123dB.

The ETRX3 is a low power 2.4GHz ZigBee module series integrating a 2.4 GHz, IEEE 802.15.4 compliant transceiver with 192k of flash, 12k of RAM, and many advanced peripherals.

The EM357 used utilizes an efficient architecture that exceeds the dynamic range requirements imposed by the IEEE 802.15.4-2003 standard by over 15 dB. The integrated receive channel filtering allows for robust co-existence with other communication standards in the 2.4 GHz spectrum, such as IEEE 802.11 and Bluetooth.

The ARM® Cortex M3 microprocessor is optimized for high performance, low power consumption, and efficient memory utilization making it ideal for use in ZigBee applications. To maintain the strict timing requirements imposed by the ZigBee and IEEE 802.15.4-2003 standards, the EM357 integrates a number of MAC functions into the hardware handling automatic ACK transmission and reception, automatic backoff delay, and clear channel assessment for transmission, as well as automatic filtering of received packets.

The ETRX3 works from a 2.1v to 3.6v supply and active power consumption is reduced by over 20% compared to the ETRX2. In deep sleep mode, current consumption is reduced to 800nA and further reduced to 400na if the self wakeup feature is not enabled.

The ETRX3 features all the advanced software already present on other Telegesis ZigBee modules such as the Telegesis AT command set which allows the designer to use the functionality of the EmberZNet stack without the need for complex embedded code. Development is also made easier by the addition of an integrated JTAG and debugging interface.

As with all our modules, the ETRX3 is designed to be easily integrated into a design without the need for RF or embedded expertise. Using the latest version of Embers Znet PRO meshing technology the ETRX3 allows you to add the latest meshing radio technology without complex software engineering.

ETRX3 module features

• EM357 ZigBee SOC featuring 32-bit ARM® Cortex-M3 processor
• Dimensions 19mm x 25 mm x 3 mm
• 192k of Flash, 12k of RAM
• Estimated RX Sensitivity -99dBm (-100dBm Boost)
• Estimated TX Power 3dBm (5dBm Boost)
• 105dB link Budget
• Est Current Consumption: 20% better compared to ETRX2
• 128µS Wakeup
• Improved Hardware MAC Acceleration
• JTAG Interface for Programming and Debugging
• Improved Peripherals (ADC, timers etc.)
• Chip Antenna and U.FL coaxial Connector
• FCC Approval, tested for European Regulations


The ETRX3 will be available in commercial quantities during the third quarter of 2009.
The ETRX3 development kit will be released in September 2009.

Contact us for additional information on sales@iec.dk .

Download ERTX3 Product Brief


ZigBee Wireless Mesh Networking Module
Product ID: ETRX2

The Telegesis ETRX2 module is a low power, 2.4GHz ISM band transceiver, based on the Ember EM250 single chip ZigBee / IEEE802.15.4 solution.

It has been designed to be integrated into any device without the need for RF experience and expertise. Utilizing EmberZNet2.2 meshing technology, the ETRX2 enables you to add powerful wireless networking capability to your products and quickly bring them to market.

The module’s unique AT-style command line interface allows you to quickly integrate meshing radio technology without complex software engineering.

ETRX2 - Actual size - 37.75 x 20.45mm

Module Features

  • Small form factor, SMT module 37.75 x 20.45mm
  • Optional board-to-board or board-to-cable connector
  • 3 antenna options: Integrated ceramic antenna, Hirose U.FL coaxial connector or single port 50Ω pad
  • XAP2b microcontroller with non-intrusive debug interface (SIF)
  • 128k flash and 5kbytes of SRAM
  • UART interface with DMA, optional software support for hardware I2C and SPI
  • Wide supply voltage range (2.1 to 3.6V)
  • Module ships with standard Telegesis AT-style software interface based on the mesh stack of EmberZNet 2.2.
  • Can act as an End Device, Router or Coordinator
  • 12 general-purpose I/O lines and 2 analogue inputs (all 17 GPIOs of the EM250 are accessible)
  • Supports 4 different power modes for extended battery life
  • Current consumption below 1uA in deep sleep mode with self wakeup
  • Firmware upgrades via RS232 or over the air (password protected)
  • Hardware supported encryption (AES-128)
  • Tested for CE and FCC compliance (with integrated antenna), FCC modular approval
  • Operating temperature range: -40°C to +85°C
  • Options include: On board, low power voltage regulator, DC/DC regulator and watch crystal

 Radio Features 

  • Based on the Ember EM250 single chip ZigBee / IEEE802.15.4 solution 2.4GHz ISM Band
  • 250kbit/s over the air data rate
  • 16 channels (802.15.4 Channel 11 to 26)
  • +3dBm output power ( +5dBm in boost mode)
  • High sensitivity of -98dBm typ. At 1% packet error rate
  • Hardware acceleration for IEEE 802.15.4 compliant transmissions

Typical Applications

  • AMR – Automatic Meter Reading. 
  • Wireless Alarms and Security. 
  • Home/Building Automation.
  • Wireless Sensor Networks. 
  • M2M Industrial Controls. 
  • Future ZigBee systems. 
  • PC Peripherals. 
  • IEEE 802.15.4 Systems.
  • Item Tracking.

Example AT-Style Commands                                     

AT+EN Establish PAN network
AT+BCAST  Sends a Broadcast
AT+UCAST:<address> Sends a Unicast

At Power-up the last configuration is loaded from S-Registers. This can eliminate the need for an additional Host Controller. 

Download the Telegesis product range guide (pdf).