Engineers at the University of California, San Diego, have developed a new energy-efficient chip that can significantly reduce or eliminate the need to replace batteries in IoT devices and wearables. The chip, called a wake-up receiver, is designed to wake up devices only when communication and performing their functions are required. For the rest of the time, the device remains dormant to reduce power demand.
This technique is useful for applications that do not require continuous data transfer. For example, these chips can be used in IoT devices to allow consumers to immediately order household items that are about to run out. The chip can also be used for wearable health monitors, with only a small amount of reading per day. Now, the technicians who developtheseed these devices don’t know when they need to synchronize data with the network. This means that even if nothing can communicate, the device wakes up periodically to communicate. This causes the device to consume a lot of power.
The wake-up receiver is an ultra-low-power chip that continuously looks for a specific radio signal called a wake-up signal. This signal tells it when to wake up the master device. The wake-up receiver requires a small amount of energy to remain open and complete the task at 22.3 milliwatts. That’s about half a millionth of the power needed to run LED night lights.
A feature of this design is that it targets radio signal target frequencies higher than those detected by other wake-up receivers. These signal frequencies are 9GHz and fall within the frequency range used by satellite communications, air traffic control and speed detection. Antennas, transformers, and other off-chip components can be reduced by aiming at higher frequencies.