What started off as RFID for security purposes has, in a little over 20 years, become a universal technology that enables features that many consumers can’t imagine going through daily life without. Today, we’re discussing NFC Wireless Charging and what design considerations should be made for three of its fastest-growing product categories…
What is Near-Field Communication (NFC)?
First thing’s first: NFC is a data-protocol that operates at 13.56MHz and can deliver data at up to 10 cm of separation between transmitter and receiver. Today, most know NFC as the technology that drives cashless payments, inventory tracking, time and attendance records, transportation ticketing and verifies products (i.e. tap-to-pay, merchandise security tags, authorized visitor tracking, digital boarding passes and even vape pod authentication, respectively). The maximum data transfer rate of NFC is 848 kbps.
NFC Charging utilizes NFC to transmit small amounts of wireless power and data from a single coil. In May 2020, the NFC Forum, the global standards and advocacy association for NFC technology, announced the ratification of the NFC Charging Specification (WLC) 1.0 allowing up to 0.5W and 106kbps to small devices.
Sound like an incremental innovation? Think again.
The ratification of NFC WLC, signaled that wireless power would soon be adopted by the thousands of devices that were previously deemed “incompatible” with wireless power, due to: 1) having too small of form-factors for Qi wireless charging technology – the leading wireless power technology in mass production today and; 2) the lack of regulated, commercialized RF-based solutions for charging lower-power devices at a distance (especially ones that are constantly moving).
Fast-forward to Oct. 2021, when the NFC Forum rolled out an update to their specification. NFC WLC 2.0 increases the transmitted power levels to 1W or about 500mW received; supports even smaller antenna sizes; and allows for “reverse” wireless charging between two NFC-enabled devices.