October 11, 2017 | News Brief | Silicon Labs has introduced a comprehensive reference design to simplify the development of USB Type-C rechargeable lithium ion battery packs used to power smartphones, tablets, laptops, headphones, and other portable devices. The reference design includes everything developers need to create dual-role port (DRP) applications with USB Type-C power delivery (PD), accelerating the development of new USB Type-C battery packs or migrating existing USB Type-A battery pack designs to USB Type-C. Silicon Labs’ USB Type-C Battery Pack Reference Design includes a development board, USB Type-C PD stack, example code, schematics and a hardware manual.
The DRP battery pack reference design takes advantage of the PD stack included in Silicon Labs’ Simplicity Studio. The stack enables developers to make high-level function calls to negotiate and send USB Type-C messages to send or receive power. The flexible board design gives developers complete control over the battery application and includes a button used to change the power direction between sink and source mode.
The Silicon Labs EFM8 Busy Bee MCU on the development board serves as a PD controller and provides exceptional design flexibility by negotiating a variety of power schemes. The reference design supplies 15 W (3 A at 5 V) of power and charges at 1.8 A. The PD stack uses only a portion of the MCU’s capabilities, leaving many peripherals, memory and processing power available for developers to control regulators and power ICs, detect orientation, control switches, update other hosts on status and more. By using the EFM8 Busy Bee MCU as a PD controller, developers can incorporate other useful functions including an integrated temperature sensor and an analog-to-digital controller (ADC) to monitor the battery pack’s temperature and voltage to prevent overheating or overcharging.