Sharp Arrow targets ultra low power
The Oryx Board is based on low-power components from Sharp, NXP, Analogue Devices and Linear Technology. The main power consumer is the NXP Cortex-M0 based LPC11U14 MCU which, with a clock rate of its M0 kernel at 50MHz, requires 8mA. The temperature sensors are in next place, also by NXP (I2C active type) with a maximum input of 300µA and RTC at 200µA.
Yet, in normal operating mode, the system power input is reduced to around 2.37mA mainly by reducing the processor frequency to 12MHz. However the stand-by consumption is crucial to the battery life and consequently the operational readiness of mobile devices.
In this respect the Oryx Board has proved to be a true power-saving performer. In the sleep mode with only basic functions of the CPU active and with the display switched off, the whole system only requires 366µA.
The Deep Power Down Mode considerably reduces power input once again to a level of only 2.27µA. In order to awaken from the deep sleep, the reference design contains an acceleration sensor that signals to the CPU to start operating as soon as the device is moved. This feature is useful for the development of TV or audio equipment remote controls that are left lying on tables unused for long periods of time.
Only when these remotes are picked up do they switch to operating mode. In this state the system can in theory also be recharged by solar cells under synthetic light. The low-power input of the Oryx Boards of maximal 8.57mA shows that, in theory, portable devices such as testing and measuring devices in the medical and industrial sectors, sport and fitness computers, mobile POS input terminals, toys or remote controls can be developed as energy self-sufficient systems.
High-performance mini solar panels, such as those offered by Sharp, supply power of up to 390mW in sunlight and even a good 1mW in indoor lighting. Enough to charge in Deep Power Down Mode a lithium ion battery or a super capacitor which supplies the application in operation, thus guaranteeing continuous readiness for the application to be used – all without changing the batteries or using an external charger.
The Oryx Board is available from November 2011 onwards exclusively from Arrow Electronics. All components integrated in the reference design are also available at Arrow Electronics.
If you enjoyed this article, you will like the following ones: don't miss them by subscribing to :
