EFM32GG11™ Giant Gecko Series 1 32-bit MCUs Silicon Labs EFM32GG11™ Giant Gecko Series 1 32-bit MCUs are ARM® Cortex®-M4 based 32-bit microcontrollers (MCUs). The EFM32GG11 provides robust security via a unique cryptographic hardware engine. The engine supports AES, ECC, SHA, and True Random Number Generator (TRNG). Features include an SD/MMC/SDIO controller, Octal/ Quad-SPI memory controller, 10/100 Ethernet MAC, and dual CAN bus controller.