Day 6 - 27 July
- Sara Faour
Ultra-low power circuits and quantum computing paradigms
Prof. Massimo Macucci
Power consumption is one of the most important issues in IoT devices, since they often need to operate without connection to an external power supply or to operate for a very long time on a battery that cannot be replaced.
Strategies to reduce power consumption include:
having very short active times,
smart circuit design,
transferring most of the data processing to master nodes that have no strict energy limitations, but this may not be enough, and we need to act upon device technology
Empirical scaling law by Moore has driven the development of micro and nanoelectronic technologies
in the last 5 decades, but power dissipation is the single most important obstacle.
clock frequency saturates at a certain power, and this is not an issue of silicon, it is an issue of power dissipation per surface where at a certain power it is impossible to remove heat and circuit will get melted. → scaling is not ideal
The response of Intel and other microprocessor manufacturers was to increase the number of cores, but this is not the same as increasing clock speed
There are a number of reasons why the supply voltage cannot be reduced, but one of the most important is keeping a large enough Ion/Ioff ratio → This ratio is larger for smaller transistors
in ideal cases Ion should be 1000 times higher than Ioff
Subthreshold slope
Tunnel FET operation
The ON and OFF transition currents are sharper for FET than MOS due to low band gap material which is not suitable for MOS devices → exponential decrease/increase.
The three-terminal device concept
Bob Keyes’s rules for three-terminal devices:
A device must be one-directional
A device must have power gain
The output of a device must be ableto directly drive the input of an analogous device
Embedded High Performance Computing: the EuroHPC and the European Processor Initiative
Prof. Sergio Saponara