Analog Devices ADUCM3027BCPZ, 32bit ARM Cortex M3 Microcontroller, ADuCM, 26MHz, 128 kB Flash, 64-Pin LFCSP

The ADuCM3027/ADuCM3029 microcontroller units (MCUs) are ultra low power microcontroller systems with integrated power management for processing, control, and connectivity. The MCU system is based on the ARM Cortex-M3 processor, a collection of digital peripherals, embedded SRAM and flash memory, and an analog subsystem which provides clocking, reset, and power management capability in addition to an analog-to-digital converter (ADC) subsystem

Ultralow power active and hibernate modes
Active (full on mode) < 30 μA/MHz (typical)
Flexi™ (core in sleep, peripherals active) < 300 μA (typical)
Hibernate (with SRAM retention) < 750 nA (typical)
Shutdown (optional RTC active) < 60 nA (typical)
ARM® Cortex®-M3 processor with MPU
Up to 26 MHz with serial wire debug interface