Once the hot topic of dedicated conferences and standards battles, wireless charging has become part of the furniture, but there is still significant work to be done to apply it effectively to many ultra-low power IoT devices, and potentially to use energy harvesting to replace batteries altogether. A decade of work on the latter area has not produced mainstream results, but every so often a start-up sticks its head above the parapet with a new approach, as Atmosic has done in recent months with the launch of two Bluetooth 5.0 system-on-chip (SoC) products which include support for energy harvesting, and target ultra-low power IoT applications.
Wireless Watch’s sister service, Rethink IoT (RIoT) interviewed Srinivas Pattamatta, the company’s VP of business development, who explained that the company was founded in 2016 by a group of engineers from Atheros, the WiFi chip company that Qualcomm bought for $3.6bn in 2011.
The founders have been involved in low power wireless chips for 20 years and are now guided by an advisory board including Alphabet chairman John Hennessy and Atheros founder Teresa Mang. Having just completed a second round of funding, Atmosic has now raised close to $50m, and having delivered the chips, the 50-strong team is focused on revenue growth.
Atmosic’s core business is in Bluetooth 5.0 chips, optimized for ultra-low power consumption. These have three main sources of differentiation.
One is the claim that the chips can achieve five times lower active power consumption than rivals, and can extend battery life by 3-5 times. Pattamatta said that Atmosic was sampling these chips in October 2018, and has started shipping, in low volumes so far, to several customers.
The second key area of focus is on chips that provide ‘on-demand receive’ capabilities – an auxiliary receiver that acts like a pair of ears that never sleep, allowing the main device hardware to be fully put to sleep. This secondary receiver listens for a specially coded Bluetooth packet, which will wake the device. Atmosic claims that this can provide anywhere between 10 and 100 times power savings, compared to competitor products.
The third element is managed energy harvesting. Atmosic can harvest energy from RF, light, thermal and motion, looking to the potential to create completely battery-free devices, or to implement a ‘Forever Battery’ that will help to trickle-charge a battery in a device.
Pattamatta said that in consumer applications, the user doesn’t typically mind changing a battery, but in business deployments, with large numbers of devices and truck roll costs, the Forever Battery proposition becomes very attractive. He claims that the technology will extend battery life by 7-8 years, meaning that most customers will be upgrading the application itself before they need to change the battery.
RIoT asked about the general reputation of energy harvesting in the industry, pointing to gradually declining claims from start-ups like Ossia, and the slow progress of others like EnOcean. Pattamatta agreed that energy harvesting has had a bad reputation in the past 10 years, but pointed to Atheros’ experience in WiFi as a possible comparison. He noted that 12 years ago, Atheros struggled to achieve 54Mbps in demonstrations that had devices just two feet apart. Now, WiFi can hit multi-gigabit speeds in commercial deployments, and similarly, Atmosic thinks RF energy harvesting is in the same early difficult period that WiFi survived – and has a similar renaissance ahead (though it is worth remembering that WiFi received its most important kick from Intel’s support when it embedded the technology in laptops via its Centrino chipset. Energy harvesting may need a similar big champion).
Atmosic is choosing to target devices that run on AA batteries, and is deliberately avoiding those at the higher end of the power consumption tables. Pattamatta said that the trick is not in the actual harvesting, because the laws of physics dictate that a large amount of any emitted signal’s energy is lost during transit. Rather, the trick is in cutting the amount of energy needed during operations to the absolute lowest amount. He likened this to two marathon runners – both complete the race, but between races, the Ossia approach must consume vast amounts of calories to recuperate, while the Atmosic runner will get by on just a power bar, because it consumed less energy during the actual running.
As for customers, there are two main segments – consumer electronics, and industrial and enterprise. On the consumer side, the main current targets are remote controls, computer peripherals, door locks, and a few smart home applications like switches. Pattamatta said that he could not disclosed names currently, but there are a couple of live products in the USA and in Japan, and a few in China. On the industrial side, Bluetooth beacon applications are set to ship within the next 6-9 months.
Atmosic recently announced a partnership with Tonly, a division of Chinese electronics giant TCL, which is the number-one wireless module producer in China. Atmosic believes this alliance positions it well to attack the Chinese market.
The current focus on Bluetooth 5.0 remains, thanks to its new support for longer range personal area networks, and for mesh networking. It does have slightly lower power consumption than other short-range protocols like ZigBee, though Pattamatta believes Atmosic could get equivalent performance in Zigbee and Z-Wave if it decides to branch out in that direction in future.
For now, the main challenge is to stay ahead of rivals. Pattamatta thinks others will catch up with Atmosic’s power performance, pointing to Nordic Semiconductor’s 9mA design, which was then beaten by Dialog’s 4mA, though both are now some way behind Atmosic’s claims of 0.9mA usage.