RSS Feeds
Low-Power Microcontroller Could Give Boost to Energy Harvesting
Active power consumption is three times better than predecessors
Charles J. Murray -- Design News, August 25, 2008
Texas Instruments Inc. is taking aim at power reduction in the newest generation of its well-known MSP430 microcontroller, which is said to offer an active current consumption that's three times better than its previous generation.
TI engineers say the power reduction could serve to enable some select portable applications to operate without batteries, instead using so-called "energy harvesting" to power small devices.
"The potential for this is really quite high," says Kevin Belnap, product marketing manager for the MSP430 group at TI. "The active power is so low, it gets you down to the point where applications like energy harvesting really begin to make sense."
The latest generation of TI's MSP430 microcontroller is said to offer the industry's lowest power consumption for devices operating up to 25 MHz, offering 160 µA/MHz (microamps per megahertz) active power consumption and 1.5 µA in standby. TI engineers say the active power figure is three times better than its predecessor, even while using twice as much flash memory. By designing the new MSP430 in this way, the company plans to eventually integrate more peripherals, particularly USB and RF capabilities.
"With the very low active current of this device, it just makes a lot of sense to integrate RF and USB," Belnap says.
TI adds some customers are already using the device in energy harvesting. AdaptivEnergy, a maker of miniature piezoelectric actuators, is using it on a product called the Joule-Thief, which collects and stores energy from tiny mechanical vibrations and then uses the harvested energy to power the MSP430. Enough energy is harvested from the application to implement a full Zigbee wireless system without batteries. Belnap says such applications wouldn't be possible at the higher power draws of earlier microcontrollers.
Other applications for the device include home security systems, remote metering and portable medical equipment, all of which could possibly use smaller batteries as a result of the MSP430's miniscule current draw. Some energy harvesting systems could also employ the new MSP430 to operate without batteries, instead drawing power from solar cells or even human body temperature.
