Norway's Energy Micro has revealed further details of what it claims will be the most power efficient ARM microcontroller yet, including details of its autonomous peripheral mode.
The processor is an ARM Cortex-M3 called EFM32.
"The M3 is a good starting point when you are making a low power microcontroller," CEO Geir Forre told Electronics Weekly. "We have been able to implement a Cortex-M3 whose active power consumption with flash active will be much lower than anyone else's Cortex-M3."
Forre is still not putting figures on active power consumption, awaiting the product's official launch, but he did tell EW that there are several low-power modes and quiescent current will be "sub-100nA with everything shut down".
Of particular interest is the chip's 'Energy Mode 1' which allows peripherals to act autonomously with the CPU core completely shut down.
Talking of an on-chip serial transceiver, Forre said: "Without CPU intervention, it can receive and put data directly into RAM, and it can transmit directly from RAM. At 10kbit/s, a large amount of data can take a long time."
The ADC is another autonomous peripheral. "It can convert at a specific time, you can preset the time with the real-time clock," said Forre. "Most of the peripherals can have some form of automation."
The list includes: DMA, hardware 256-bit AES, external bus interface, integrated high frequency oscillators, ADC and DAC.
All autonomous activities are either data-triggered, or time-triggered by internal clocks.
