‘Keep alive’ device draws power from sensor output

The developers say the device will allow designers to create circuits that can perform continuous monitoring without using battery power and to implement wireless wake-up with zero receiver power. Requiring no power supply, the chip uses a fraction of the power in the sensor’s output signal.

Dr Bernard Stark, from the Bristol Electrical Energy Management Research Group, said: “The UB20M provides sensing that is continuous and free. This is because it is able to respond to minute quantities of power from unpowered sensors. No battery or other power is needed for the device to stay alive and listening and battery maintenance is therefore reduced or not needed. We are now actively seeking commercial partners to use the voltage detector chip in their product.”

According to the team, the voltage detector uses more than 1000 times less energy than existing detectors to create a turn-on signal – 5pJ from around 0.5V. Because many sensors can provide this, listening is effectively free.

Potential applications are said to include: battery-driven sensors and monitoring systems; remotely-powered sensors; the elimination of mechanical switches; and the generation of sensing data only when useful data is available.