By Mark Hopgood
Electronics and H2O are inherently poor bedfellows, as anyone with even the most elementary understanding of power dynamics could tell you. This has never stopped humans from developing new devices that challenge the diametrically opposed relationship between electricity and water, whether that includes crafting watches that can withstand submersion dozens of meters into the sea or meteorological tools that need to stay powered even when exposed to extreme weather events.
This has become an increasingly prescient topic as IoT innovation looks to prompt “cord-cutting” in a number of scenarios, including removing the need for wired chargers to keep portable IoT devices “always on.” In the context of waterproof IoT tech, removing the port that connects a device to a wall-mounted charger eliminates one less opening from the design that could expose electrical currents within the technology to water when submerged. This works to tighten up the overall form of any IoT device, which goes a long way in devising IoT tech that water truly cannot penetrate.
Wireless charging is already a capability for a number of technologies, including smartphones, tablets, laptops and wearable devices, just to name a few consumer examples. As part of our recently announced partnership with Energous, we’ve developed the DA4100 RF-transmit IC to help significantly simplify the implementation of WattUp wireless power transmitter systems, ultimately making them smaller and more cost-effective. This helps support near-field (within a few millimeters of a charging pad), mid-field (within two to three feet) and far-field charging ranges of up to 15 feet, ensuring a wire-free experience for all device users that is a requirement of true IoT.
For waterproof IoT technology, the most obvious devices that will benefit from wireless charging may be the wearables – like fitness trackers and wireless earphones – that have become a staple among athletes and casual gym-goers alike. If a swimmer wants to track their heart rate while training via an app on their expensive wearable device, they will likely feel more comfortable bringing this pricey tool with them into the water if the design is completely and seamlessly sealed, even if the product is advertised as “waterproof.”
Wearables are only the beginning, as the ability to wirelessly charge any IoT device that lives in a humid environment is also critical. In industrial settings, for instance, many of the beacons and sensors that will be fueling Industry 4.0 may be employed on manufacturing lines where the extremes in heat and humidity put a strain on traditional device configurations. Moisture is less likely to permeate a device with a completely shielded form, so the ideal casing for one of these sensors would house a power management IC that is receptive to RF-transmit charging. By placing multiple wireless charging transmitters in the vicinity of these sensors, challenges related to wiring and backing up these sensors can be quickly and cost-effectively resolved.