Silicon Labs has just rolled out a host of new Zigbee-based Ember ARM microcontrollers targeted at wireless Internet of Things applications for smart energy and automation in the home.
According to Geir Førre, senior vice president and general manager of Silicon Labs’ microcontroller and wireless products, the new EM358x SoC family provides additional flash and RAM memory options to meet the needs of larger, more complex smart energy and home automation designs as well as USB connectivity and a local storage bootloader to help developers reduce bill of material (BOM) cost and system complexity.
Because wireless mesh based IoT designs often require multiple processors, he said, the EM358x family includes six SoC products that combine a 2.4 GHz IEEE 802.15.4 RF transceiver, an ARM Cortex-M3 processor, 256 kB or 512 kB of flash memory, and 32 kB or 64 kB of RAM with powerful hardware-supported network-level debugging features.
“The additional memory minimizes the need for a separate system processor,” he said, “enabling developers to collapse some or all of their multi-processor designs into a single ZigBee SoC to reduce BOM cost and the size of the final product.”
By offering larger flash and RAM memory options, Førre said, the EM358x SoC family enables developers to future-proof smart energy applications such as smart meters, which often require more code space to store new firmware and additional RAM enabling product lifespans of up to 20 years.
The EM358x SoC family also incorporates an on-chip USB peripheral to simplify system programming and eliminate the need for an external USB controller, further reducing system cost.
“Many ZigBee-enabled devices require a USB connection to provide an easy-to-use serial application interface or a service port to the device,” he said. “The USB port can also be used to download new firmware images onto the device, reducing maintenance cost. “
The new SoC family features a local storage bootloader that makes it possible for embedded software to be field-upgraded after the Ember ZigBee-enabled product leaves the factory. He said the new bootloader capability eliminates the need for external flash memory to support over-the-air upgrade images by using the SoC’s on-chip flash to store firmware images for bootloading, reducing the component count, cost and size of the product.
This means, said Førre, that smart meters or security sensors based on EM358x SoCs can be easily field-upgraded as new platform features are deployed, avoiding costly truck rolls.
The EM358x SoCs offer a configurable total link budget up to 110 dB and the devices’ 8 dBm transmit power eliminates the need for an external power amplifier (PA) in many applications, especially in Europe and Asia, where regulatory limits do not allow much higher transmit power.
Because radio systems must operate in the presence of many types of interference, the EM358x SoCs incorprate the ability to co-exhist with other 2.4 GHz devices. ThetEM358x SoCs are tightly integrated with the company's EmberZNet PRO protocol stack.