Designers of portable Li-ion battery-powered electronics now have a simplified and more flexible way to add a USB Type-C (USB-C) charging system to their products with the MAX77860 3A switch-mode charger from Maxim Integrated. This USB-C buck charger provides the industry’s first integrated USB-C port controller and charger to eliminate the need for a separate host controller, simplify software development and reduce overall bill-of-materials (BOM) costs for applications such as financial point-of-sale terminals, power banks, industrial computers, scanners, radios, medical devices, charging cradles, portable speakers and game players.
A wide range of consumer electronic devices are migrating to USB-C interfaces to support rapidly advancing communication and battery-charging capabilities, as well as smaller design size. In current designs, the host microprocessor is needed to detect the current level and configure the charger’s input current limit. While PCs, laptops and cell phones have driven early adoption, USB-C adoption rates are expected to grow at 8.5 percent a year through 2020 thanks to usage in other classes of portable devices, according to IDTechEx.
To reduce design size as well as simplify the system hardware and software design, the MAX77860 integrates USB-C configuration channel (CC) port detection and a battery charger for 15W applications. These integrated functions allow battery charging at the fastest rate possible under the USB-C specification and contribute to 30 percent smaller design size while also simplifying software development. The CC pin detection feature also shortens the design effort by eliminating the need to support end-to-end USB port connection and allowing charging to start automatically.
Key Advantages
- Highly Integrated: Eliminates a separate port controller and many discrete components. Reduces the size of an inductor and a capacitor due to a high switching frequency of 2MHz/4MHz, resulting in a solution size that is 30 percent smaller than the closest competitive device. This high level of integration also reduces overall BOM costs.
- High Efficiency: High-efficiency buck reduces heat dissipation with more than 93 percent efficiency and up to 3A charging capability.
- Design Flexibility: Backward compatibility allows designs to work with both USB-C and legacy BC1.2 or proprietary adapters. Integrated analog-to-digital converter (ADC) frees up resources in the microcontroller, while providing accurate voltage and current measurements.
Availability and Pricing
- The MAX77860 is available at Maxim’s website for $3.03 (1000-up, FOB USA); also available with select authorized distributors
- The MAX77860EVKIT# evaluation kit is available for $70
