Currently, one of the main limitations of developing gadgets and sensors for smart home is the fact that they’re hungry for energy and are completely reliant on an external energy source. This explains why all sensors available to the retail market today are so big and clunky.
Even the tiniest “coin battery” ads so much to a sensor’s size and weight. Besides, the need for battery replacement limits the design of internet of things. It looks like the California-based semiconductor manufacturer Cypress has got a solution. The company was founded by an American scientist and semiconductor guru T.J. Rogers. Recently they came up with an ingenious new architecture for making tiny sensors. They documented the method in this article, in case you fancy a more in-depth look into this geekiness.
The sample smart sensor is just 24mm in diameter, no bigger than a 25c coin. The most revolutionary part is that the sensor doesn’t have a battery. It relies on two autonomous energy sources to deliver electricity for its own operation – a tiny 15mm photovoltaic solar panel and a state-of-the art energy harvester that accumulates energy from stray microwaves.
The excess energy is stored in a capacitor thus eliminating any need for a battery.
It makes the most of the up and coming Bluetooth Low Energy (BLE) technology meaning that it only needs tiny amounts of energy to transmit information. The BLE module used on this sample sensor has a 32-bit processor on board, so its “brain power” is pretty impressive. Since it’s using BLE and can’t transmit to huge distances (for obvious reasons), the new sensor architecture can be used to build node sensors that form a wireless chain of communication in order to deliver information to a bigger sensor or a hub. That doesn’t matter much for smart home installations as transmission distances are never too long. The opportunities are endless. These sensors can be used to feed information about temperature, moisture, light and other factors that are important for a modern smart home.