Atmel's USB product line consists of hubs and compound microcontroller devices. The hub controllers are state machine-based designs and require no firmware for operation. Atmel supplies a full-featured hub controller and a low-cost hub controller. The compound devices are hubs with an embedded function controller and a very powerful 8-bit AVR RISC microcontroller to support downstream device control functions.

All Atmel's USB hubs and device controllers contain on chip 3.3V power supply and operate with a 6 MHz crystal to simplify the design of USB peripheral devices. This eliminates noise- producing 48 MHz circuits and makes product radiated noise certification easier. In addition, all the Atmel USB Controllers can be powered directly from the bus without an external voltage regulator.