Lowest-power processor ever? Possibly
April 22, 2015
I always raise an eyebrow when a see that a company has "reached a new level of performance" or something like that. In a discussion earlier today, I...
I always raise an eyebrow when a see that a company has “reached a new level of performance” or something like that. In a discussion earlier today, I was told that a new generation of a production achieved 80 percent better performance than the last generation. My immediate reaction was, “I guess they did a poor job of engineering on the last generation.” Call me a cynic.
Anyhow, fast forward to the latest “lowest ever” device that was just announced. If the claims they’re making are true, they may be onto something. The part I’m talking about is Atmel‘s Cortex M-based processor, which boasts a power consumption level of 35 µA/MHz in active mode and 200 nA in sleep mode. Called the SAM L family, it’s part of the company’s SMART 32-bit ARM-based MCU family.
Such a device allows for applications that will benefit from going years (yes, years) without having to swap out or recharge the battery. For example, this would work well in fire alarms, healthcare, medical, wearable, and devices placed in rural, agriculture, offshore and other remote areas.
One device, the SAM L21, combines low power with flash memory and SRAM. That combination is large enough to run both the application and wireless stacks. This is a great way to integrate an Internet-of-Things application with fewer components.
Atmel also implements something called Sleepwalking (that’s a great name). This means that peripherals can request a clock when they need to wake up from sleep modes and perform tasks without having to power up other subsystems.
Another “must have” in my opinion is an evaluation board/development kit. Thankfully, Atmel has its Xplained Pro, an eval kit with an onboard debugger and standardized extension connectors. The Xplained (non Pro) version is a low-cost, easy-to-use, fast prototyping, and evaluation platform. The kit can be customized with various expansion boards.