Called Wireless Gecko, they integrate an ARM Cortex-M4 core with a 2.4GHz radio, hardware cryptography, stacks for Thread and ZigBee, and radio interface software for proprietary protocols and Bluetooth Smart.
There are three product ranges: Blue Gecko for Bluetooth Smart, Mighty Gecko for ZigBee and Thread, and Flex Gecko family for proprietary wireless protocols. Of these, Mighty products are the most able, with 256kbyte of flash, to deal with the extra complexity involved in mesh networking. All products also have sub-GHz capability. Flex Geckos make use of the firm’s new RAIL (radio abstraction interface layer) software which is intended to ease the migration of existing application code.
The firm has included the floating point option in its M4s, and is claiming 63µA/MHz active mode consumption.
Radios are a Silicon Labs speciality. These ones integrate a software-programmable power amplifier and balun, and can output between -30dBm and +19.5dBm. “It doesn’t mean you will be transmitting 20dBm everywhere, it is not even legal in some markets,” pointed out Daniel Cooley, marketing v-p at Silicon Labs.
The crypto accelerator encrypts and decrypts Internet security protocols including TLS/SSL with minimal CPU intervention. It supports AES with 128- or 256-bit keys, elliptical curve cryptography (ECC), SHA-1 and SHA-224/256.