Low power USB 2.0 controllers have port options and small footprint
USB 2.0 hubs claimed to consume the least amount of power and require the smallest real-estate footprint in the industry have been announced by Exar. The XR22404 and XR22417 are designed for applications where power consumption and board space are a concern such as docking stations, point-of-sale terminals, USB port expansion, test instrumentation, factory automation and other industrial applications, says the company.
The XR22404 is a USB 2.0 four-port hub controller that can be configured for downstream device charging. It supports USB Battery Charging Specification 1.1 and 1.2. It operates from either 3.3 or 5.0V supplies, allowing bus- or self-powered operation without an external LDO. The controller is available in a 4.0 x 4.0mm, 24pin QFN package, making it the smallest USB 2.0 four-port hub controller on the market, according to the company. It is also available in a 28pin SSOP.
The XR22417 is a USB 2.0 seven-port hub controller that uses multiple transaction translators (MTT) for the highest possible bandwidth. It is also designed to minimise power and size to meet the challenging constraints facing connectivity and interface designers. It is available in a 64pin LQFP as well as a smaller, 48pin LQFP.
Both controllers are compatible with standard software drivers and include LED indicators to simplify implementation and attach to upstream ports at high-speed (480Mbit/s) or full-speed (12Mbit/s). The downstream PHYs support high-speed, full-speed and low-speed (1.5Mbit/s) on each port.