The challenge

A vast amount of energy is wasted by televisions, radios, security alarms, wearable monitors, traffic systems and other domestic and consumer electronic systems when they are held on standby or sleep mode, waiting to detect and react to a remote signal. 

Not only does this represent a significant drain on economic budgets and the environment, it also compromises the lifetime and functionality of electronic devices.

As an extreme example, an earthquake detector could be held in sleep for years, until a tremor caused the chip to wake its host.

What we're doing

Engineers from the University of Bristol have come up with a solution that has the capacity to reduce this power drain and could have implications for developing alternative circuit systems in mains powered equipment, battery driven devices and remotely powered sensors.

Unlike other systems, the UB20M patent-pending chip is purely sensor-driven, which means it uses wireless sensor nodes as opposed to battery or mains power supply, thereby eliminating the need for standby power.

The sensor, otherwise known as a Keep Alive Device, is continuously monitored, using power from its own output signal to detect and respond to changes in the environment without expending any energy until required.

How it helps

At just 2.9mm in size, the voltage detector chip is small enough to fit into many autonomous devices and uses 1,000 times less energy than existing low power microcontrollers – just five pico-joules of energy, or half a volt, is needed to create a turn-on signal.

“We are now working on ways of bringing other power drains such as data-capture, computation, and transmission, to within the power budget of a sensor, completely eliminating batteries from sensor nodes,” says Dr Bernard Stark.

The researchers are keen to help companies evaluate the voltage detector chip in their products, and to share these devices with other research groups. To register your interest, contact Dr Bernard Stark at bernard.stark@bristol.ac.uk.