Some critics doubt the battery in the Apple Watch will last a full day. Short battery life has become the bane of existence for many smartphone users too, but Atmel has released a new microcontroller that can power Internet Of Things devices for more than a decade on a single charge.
Don't throw away your chargers just yet. Obviously, we're still a long way from a phone that can last 10 years on one charge, but the new microcontroller will likely be used in thousands of Internet Of Things (IoT) devices with low power consumption.
Atmel's SAM L21 family of microcontrollers, which are powered by the ARM Cortex-M chip, are designed for use in devices with extremely low power consumption like fire alarms, building sensors and even small wearables. Atmel says the new microcontrollers consume only a third of the power of comparable products on the market.
The microcontrollers are specially designed for devices that sleep most of the time and wake up when something happens. The chips use just 35 µA/MHz while active, and 200 nA while in sleep mode, apparently consuming less than 900 nA while retaining 32 KB of SRAM and running a real-time clock and calendar. It's easy to see how something could last decades if it's only using 0.0000002 Amps when it's sleeping — that's so little that it can actually run off energy drawn from your body.
Of course, this all means that the microcontrollers don't have a huge amount of processing power. The specs show a 42 MHz Cortex M0+ CPU core, 256 KB of Flash memory, 32 KB of static RAM and 8 KB of separate low-power static RAM. That's not going to power an Apple Watch or an iPhone, but it's plenty to run small programs that read and record sensors and send automatic messages or tweets.
"The surge in popularity of battery-powered electronics has made battery life a primary system-design consideration," said Andreas Eieland, Atmel director of product marketing. "In extreme cases, the desire is not to run off of a battery at all but to harvest energy from local sources to run a system — which requires the utmost power frugality."
Devices such as fire alarms, health care, medical, wearable and devices placed in rural, agriculture, offshore and other remote areas could have their battery life extended from years to decades with the new microcontorllers.
The SAM L21 chips are already being sampled by customers. Design and development tool information is available here, and production quantities of the chips are scheduled for a September 2015 release.
