USB 2.0 HSIC Hi-Speed 4-Port Hub Controller
Datasheet
Chapter 5 Modes of Operation
The device provides two main modes of operation: Standby Mode and Hub Mode. The operating mode
of the device is selected by setting values on primary inputs according to the table below.
Table 5.1 Controlling Modes of Operation
RESET_N
INPUT
RESULTING
MODE
SUMMARY
0
Standby
Lowest Power Mode: No functions are active other than monitoring the
RESET_N input. All port interfaces are high impedance. All regulators are
powered off.
1
Hub
Full Feature Mode: Device operates as a configurable USB hub with battery
charger detection. Power consumption is based on the number of active ports,
their speed, and amount of data transferred.
Note: Refer to Section 8.4.2, "External Chip Reset (RESET_N)," on page 56 for additional information
on RESET_N.
The flowchart in Figure 5.1 shows the modes of operation. It also shows how the device traverses
through the Hub mode stages (shown in bold.) The flow of control is dictated by control register bits
shown in italics as well as other events such as availability of a reference clock. The remaining sections
in this chapter provide more detail on each stage and mode of operation.
SMSC USB4604
25
Revision 1.0 (06-17-13)
DATASHEET
SMSC [ SMSC CORPORATION ]
