A recent study has highlighted the poor energy efficiency of existing connected devices. With the expansion of so-called internet of things, the number of smart devices will increase exponentially in the coming years and with them the need for electricity. PsiKick a startup of Virginia, however, has designed a wireless sensor that does not require external power thanks, integration of chip “sub-threshold”.
The transistor is a switch that is turned on, applying a voltage higher than the threshold, and OFF if the value is less. In fact, the transistor runs a small leakage current, even in the off state, which can be exploited to perform certain tasks. This allows reducing the waste of current associated with the on-state. The chip designed by the United States operates on “sub-threshold”, consuming 0.1% of the energy required by the chip currently on the market.
PsiKick has realized a SoC that integrates an RF circuit with low power, thus obtaining a wireless sensor that does not have to be powered by a battery. The source of energy is absorbed from the outside. The two founders of the company have successfully tested the chip in a wearable electrocardiograph powered by body heat.
The energy, very low, which is needed to turn the transistor sub-threshold, can also be obtained by small solar panels, from radio waves and the environmental movement. The SoC measuring 3.5 × 3.5 mm, operates at a voltage of 0.2 volts and consumes 400 NW on in the state. The wireless signal reaches a speed of 1 Mbps at a distance of 10 meters.