Ambiq Micro is the company that claims to have mastered the issues around building a production microcontroller in a sub-threshold logic process (where logic levels are propagated as different voltage levels, each of which is below the ‘normal’ logic ‘on/off’ switching threshold. Ambiq is now citing the EEMBC low power benchmark in its claim to have, "made history as a microcontroller that consumes less than half the energy of any other."
The benchmark, created to assist embedded designers in selecting the lowest power MCU, standardises a typical low power design workload and measures the actual energy required to complete that workload. This approach normalises the many different behaviours of MCU operation such as active current, sleep current, wake-up time, core efficiency, and cache efficiency. It then synthesises this data into a single value – the amount of energy required to complete their specific application.
Keith Odland, Senior Director of Marketing at Ambiq Micro comments, "It’s the kind of leap in performance that’s going to make the creation of completely new consumer products possible by more than doubling battery life or enabling more features to be added without increasing the power budget."
"To state that the Apollo MCU’s ULPBench results are impressive is truly an understatement, providing a practical, real-world demonstration of the device’s nearly ideal voltage transfer characteristics of its logic gates and reduced gate input capacitance," said Markus Levy, EEMBC President. "After completing certification by the EEMBC Technology Centre, we have confirmed that the Apollo MCU scores were achieved in compliance with the ULPBench standard requirements."
The Apollo MCU is based on a high-performance, 32-bit ARM Cortex-M4 processor with floating point unit. It runs at up to 24 MHz and integrates ultra-low power memory, up to 512 kB Flash and 64 kB RAM. The microcontroller comes with a set of timing peripherals, I²C/SPI master and slave ports, and a UART for communicating with peripherals and legacy devices.
Ambiq’s Subthreshold Power Optimized Technology (SPOT) platform enables the Apollo MCU to achieve its best-in-class power consumption in both active-mode and sleep-mode. The microcontroller consumes 34 µA/MHz executing instructions from flash, and sleep-mode currents can be as low as 140 nA.