The EM351/EM357x/EM358x/EM359x are fully integrated Zibgee / IEEE 802.15.4 system-on-chips. Each with integrated 2.4 GHz, IEEE 802.15.4-2003-compliant transceiver, 32-bit ARM® Cortex-M3 microprocessor, flash and RAM memory, and a range of peripherals.
The transceiver exceeds the dynamic range requirements of the IEEE 802.15.4-2003 standard by over 15 dB. Integrated receive channel filtering allows for co-existence with other communication standards in the 2.4 GHz spectrum, such as IEEE 802.11-2007 and Bluetooth. An integrated regulator, VCO, loop filter, and power amplifier further reduces the external component count. An optional high performance radio mode (boost mode) is software-selectable to boost dynamic range.
Their 32-bit ARM® Cortex-M3 microprocessor is optimized for high performance, low power consumption, and efficient memory utilization.
Choose from a wide range of embedded flash memory from 128 and 512 kB and between 12 and 64 kB of integrated RAM for data and program storage. The Ember software for the EM35xx employs an effective wear-levelling algorithm that optimizes the lifetime of the embedded flash.
To maintain the strict timing requirements imposed by the ZigBee and IEEE 802.15.4-2003 standards, these chips have a number of MAC functions, AES128 encryption accelerator, and automatic CRC handling into the hardware. The MAC hardware handles automatic ACK transmission and reception, automatic backoff delay, and clear channel assessment for transmission, as well as automatic filtering of received packets.
The Ember Packet Trace Interface is also integrated with the MAC, allowing complete, non-intrusive capture of all packets with Ember development tools.
They offer advanced power management features to enable a long battery life. A high-frequency internal RC oscillator allows the processor core to execute code quickly upon waking. Various deep sleep modes are available with less than 2μA power consumption while retaining RAM contents. To support user-defined applications, on-chip peripherals include optional USB, UART, SPI, TWI, ADC, and general-purpose timers, as well as up to 24 GPIOs. Additionally, an integrated voltage regulator, power-on-reset circuit, and sleep timer are also available.
Finally, they utilise standard Serial Wire and JTAG interfaces for powerful software debugging and programming of the ARM Cortex-M3 core. With integrated standard ARM system debug components: Flash Patch and Breakpoint (FPB), Data Watchpoint and Trace (DWT), and Instrumentation Trace Macrocell (ITM) as well as the advanced Embedded Trace Macrocell (ETM).

Target applications include :
- Smart Energy
- Building automation and control
- Home automation and control
- Security and monitoring
- ZigBee wireless sensor networking

EM35xx range options:
EM357-ZRT (RS 905-4435) with 12kB RAM, 192KB Flash in a 48-Pin QFN package
EM3582-RT (RS 905-4444) with 32kB RAM, 256KB Flash and USB in a 48-Pin QFN package
EM3586-RT (RS 905-4447) with 32kB RAM, 512KB Flash and USB in a 48-Pin QFN package
EM3588-RT (RS 905-4441) with 64kB RAM, 512KB Flash and USB in a 48-Pin QFN package
EM3591-RT (RS 905-4450) with 32kB RAM, 256KB Flash in a 56-Pin QFN package
EM3592-RT (RS 905-4453) with 32kB RAM, 256KB Flash and USB in a 56-Pin QFN package
EM3596-RT (RS 905-4457) with 32kB RAM, 512KB Flash and USB in a 56-Pin QFN package
EM3598-RT (RS 905-4466) with 64kB RAM, 512KB Flash and USB in a 56-Pin QFN package

A development kit is available EM35x-DEV (RS 904-8092).