Welcome to First Look, brought to you by Digi-Key and Maxim Integrated. Designing good power supplies has always been a challenge, and now engineers are tasked with providing multiple rails and battery charging in devices as small as earbuds, all while squeezing the longest runtime out of batteries that are getting smaller and smaller. Maxim Integrated’s MAX77654 Ultra-Low Power PMIC is designed for exactly this type of challenge and replaces three buck-boost regulators, two LDOs, and a lithium-ion battery charger. This is all integrated in a 6.52mm2 Wafer-Level Package, with a total solution size that is up to 50% smaller than alternative solutions and provides up to 20% longer battery life. The MAX77654 features a buck-boost SIMO converter that can regulate up to three outputs using a single inductor. This approach eliminates two inductors, and while the SIMO architecture requires more output capacitance to compensate for its higher output ripple, the net result is a smaller footprint, a reduced BOM count, and a lower BOM cost. The MAX77654 also integrates two LDOs, which can be used to supply audio circuits or other noise-sensitive devices, or they can be used as load switches to reduce power consumption when parts of the circuit are unused. Finally, the MAX77654 integrates a linear battery charger optimized for use with small lithium ion batteries. It offers a wide range of programmable fast-charge and termination currents, as well as a programmable battery regulation voltage. Everything in the MAX77654 has been optimized to extend battery life. The converter operates at up to 91% efficiency, and it consumes just 6µA with all 5 regulators operating, dropping to 500nA in shutdown. This enables a longer battery life and significantly lower heat dissipation than a discrete solution, reducing the PCB temperature by as much as 20°C. When designers use the MAX77654, the result is a smaller, more efficient, and more cost-effective power management solution. See you next time on First Look.
