Design Article
Piezo wireless switch: No battery, no cable, no wear
Dr. Venkatesh Sivasubramaniam, Algra AG
9/25/2012 9:07 AM EDT
Page 3
Dynasim foils are already proven for their reliability and efficient production in large quantities for keyboard-based applications. Currently, Algra is exploring new applications where the generated energy would wake up microcontrollers from a deep sleep state - see figure 7. In Sleep mode, a microcontroller is placed in its lowest current consumption state whereby the device’s oscillator is turned off, so there are no system clocks running. However, the I/O ports maintain the status they had before the SLEEP instruction was executed. In order to minimize the Sleep mode’s power consumption, the output ports should not be sourcing or sinking any current before going into Sleep mode, optimizing battery life. All the unused I/O pins should be configured as inputs and pulled either high (VDD) or low (VSS). Figure 7 shows a graph where the energy (yellow trace) from pressing a Dynasim key generates the energy required to wake up/ provide interrupts to the micro controller (green trace) and set it to a toggle state. In contrast to capacitive keys, the piezo key does not consume any power from the supply at all, allowing for a Sleep mode current that only consists of the microcontroller’s leakage. For this reason such Dynasim piezo foil applications could open new areas of optimization in power management.
About the author:
Dr. Venkatesh Sivasubramaniam is Material Scientist at Algra AG – www.algra.ch
Courtesy of EETimes Europe
See related links:
The potential of energy harvesting means there’s nothing to lose
Energy harvesting from thermoelectric sources gets a boost
Energy harvesting, wireless sensor networks & opportunities for industrial applications
Energy harvesting – Design archive
Power-management functions for energy harvesting
------------------------
If you found this article to be of interest, visit SmartEnergy Designline where you will find the latest and greatest design, technology, product, and news articles with regard to all aspects of clean technologies. And, to register to our weekly newsletter, click here.
Dynasim foils are already proven for their reliability and efficient production in large quantities for keyboard-based applications. Currently, Algra is exploring new applications where the generated energy would wake up microcontrollers from a deep sleep state - see figure 7. In Sleep mode, a microcontroller is placed in its lowest current consumption state whereby the device’s oscillator is turned off, so there are no system clocks running. However, the I/O ports maintain the status they had before the SLEEP instruction was executed. In order to minimize the Sleep mode’s power consumption, the output ports should not be sourcing or sinking any current before going into Sleep mode, optimizing battery life. All the unused I/O pins should be configured as inputs and pulled either high (VDD) or low (VSS). Figure 7 shows a graph where the energy (yellow trace) from pressing a Dynasim key generates the energy required to wake up/ provide interrupts to the micro controller (green trace) and set it to a toggle state. In contrast to capacitive keys, the piezo key does not consume any power from the supply at all, allowing for a Sleep mode current that only consists of the microcontroller’s leakage. For this reason such Dynasim piezo foil applications could open new areas of optimization in power management.
Fig. 7: The Dynasim key used to wake up a microcontroller
About the author:
Dr. Venkatesh Sivasubramaniam is Material Scientist at Algra AG – www.algra.ch
Courtesy of EETimes Europe
See related links:
The potential of energy harvesting means there’s nothing to lose
Energy harvesting from thermoelectric sources gets a boost
Energy harvesting, wireless sensor networks & opportunities for industrial applications
Energy harvesting – Design archive
Power-management functions for energy harvesting
------------------------
If you found this article to be of interest, visit SmartEnergy Designline where you will find the latest and greatest design, technology, product, and news articles with regard to all aspects of clean technologies. And, to register to our weekly newsletter, click here.
|
|
|
|
|
Navigate to related information
anne-francoise.pele
9/25/2012 10:43 AM EDT
Click on the link below to check out the collection of the Design Articles, Case Studies, Product How-To articles, Teardowns, etc... related to energy scavenging that have been published on Smart Energy Designline.
Click here: http://www.eetimes.com/design/smart-energy-design/4372778/Energy-harvesting---Design-archive
Check back frequently. The list will be updated as new articles arrive.
Sign in to Reply
Pablo Alvarez-Correa
9/25/2012 10:50 AM EDT
It would be interesting to have the chance to enlarge the pictures, many details are imposible to read...thanks in advance
Sign in to Reply
anne-francoise.pele
9/25/2012 10:52 AM EDT
Give me a few hours, and I will do that for your convenience. Thanks for your interest.
Sign in to Reply
docdivakar
10/15/2012 4:04 PM EDT
@anne-francoise.pele: any chance of seeing bigger versions of pics above? It is an interesting article and I wish you had hyperlinked figs to their larger versions...
MP Divakar
Sign in to Reply