Low power ARM7-based MCU series with 100nA power-down mode
(Technology News, 19 Mar 2008 )
Atmel has launched a series of high-performance, ultra-low power ARM7TDMI-based microcontrollers, the AT91SAM7L series, embedding power switches controlling multiple power islands and programmable voltage regulators to reduce power consumption in active and standby modes. There is a rapidly growing demand for more power efficient products that is driven by a market trend towards environmentally friendly, battery operated and portable products like media players, remote controls, weather stations, calculators, toys, control panels, thermostats and hand-held medical devices such as glucose meters, blood pressure meters and fitness monitors. The demand for green products is pushing manufacturers to consider low-power standby modes even on products supplied by the power grid. The individual standby power of audio or TV equipment is small at around 1 or 2 W per unit, but the fact that billions of these are maintained in standby mode, results in a total power consumption of thousands of megawatts.
The AT91SAM7L series features power reduction techniques for both active and standby modes. In active mode, the power consumption is optimized via a programmable operating voltage, operating frequency, and peripheral clock activity, and the use of DMA instead of the CPU for data transfers. The SAM7L operates in single supply mode down to 1.8V and consumes 0.5mA/MHz typical in active mode when executing code out of its Flash memory.
