Infineon introduces battery-free electronic lock

A new chip from Infineon is powered via NFC via the smartphone – enough to open and close small locks

Infineon’s new NAC1080 chip makes it possible to open and close digital locks without their own power supply. Instead of an internal power supply, the user’s smartphone – which is also the key – supplies the power to open it, as the chip manufacturer reports.

Both data and energy are exchanged via NFC – a process that is used, for example, for payment transactions via smartphone. Data transmission is encrypted thanks to an integrated AES128 accelerator and a random number generator.

To open the lock, the smartphone must be held directly against the lock equipped with the chip, as with other smart locks. The lock then draws energy from the built-in NFC technology through so-called energy harvesting. On average, different devices can transmit around 20 milliwatts, according to Infineon, and significantly more with some models.

Use with smaller locks

A capacitor collects the energy; the chip uses them to check whether the user is authorized and to open the lock with a small motor. According to Infineon, the technology is particularly suitable for smaller locks on office cabinets, lockers, parcel boxes or mailboxes. The duration of the opening process should be around two seconds – depending on the smartphone used and the energy transmitted.

Larger, harder-to-move locks require more energy to be transferred, which takes longer. It is therefore more conceivable to use it as an emergency option for house or hotel doors if the lock’s own energy supply fails. According to Infineon, one would then have to wait a little longer for the opening, but at least this could save the expensive key service. The first products with the chip could be on the market next year.