Ultra-compact custom power management solution for solar energy harvesting watch

27-01-2022 | e-peas | Power

e-peas has announced the completion of a major project for Swiss luxury watch manufacturer Cartier. Cartier’s new addition to its Tank watch collection contributes to long-term power autonomy, so wearers don’t have to worry about battery replacement and disposal. On average, these watches will run for 16 years – using solar power to keep constantly replenishing their battery reserves. Light incident on specific areas of the watch dial surface is absorbed by a high efficiency photovoltaic element. The e-peas PMIC then transfers the photovoltaic-generated electricity to the battery, which can be used to drive the watch mechanism.

The key performance metrics where the company’s PMICs stood out from the rest was the ability to start up and harvest power efficiently at low light levels so low indoor lighting could be enough to power the watch. Proper management of the tiny, sensitive battery was also crucial to maximizing its lifespan. The PMIC’s standby current also had to be minimal, so little power was drawn from the battery when the watch was not worn and stored in a dark place. The ultra-compact PMIC specially developed for the Tank Watch measures just 2mm x 2mm, making it smaller than any other energy harvesting solution available. The architecture employs only a few tiny external components allowing the complete solution to fit into the very limited space available in the watch.

As Arnaud Carrez, senior vice president, chief marketing officer at Cartier, comments: “For the very first time, we are presenting an original version of the Tank Watch with a photovoltaic movement, which is quite a precursor. It took us four years to develop this innovative movement with the help of Richemont Innovation and the Manufacture Horlogère de Val Fleurier. Adding advanced energy harvesting capabilities to our Tank watch collection allows us to provide our customers with a watch that meets Cartier’s standards in design and quality while further reducing the Maison’s environmental footprint on the market. its entire life cycle.

“The number of design contracts we have won for our energy harvesting PMICs continues to grow, and with this latest project, we are now taking it to a whole new level,” says Geoffroy Gosset, CEO of e-peas. “Our work with Cartier shows that we have both the technology, innovation and quality to provide cutting-edge energy harvesting solutions to the world’s best-known brands so they can gain a true competitive advantage.”

Alan A. Seibert