USB 2.0 7-Port Hub

Data Sheet Rev. 1.01

OVCJ[1] goes low, downstream facing port 1, 2, 3, and 4 would be marked as over-current. If OVCJ[5]

goes low, downstream facing port 5, 6, and 7 would be marked as over-current. Since there is only one

PWRJ pin, all ports will be switched to powered-off state at once. This is the only mode supported by

LQFP-48 package of FE2.1.

The power control mode selection is reported to the host software through the wHubCharacteristics

field, the 4th and 5th byte, of Hub Descriptor, which describes the hub's operational characteristics. Two

bit-fields would be effected – “D1..D0” for Logical Power Switching Mode, and “D4..D3” for Over-

current Protection Mode. In “D1..D0”, 00 means ganged power switching (all ports' power at the once,)

and 01 means individual port power switching. In “D4..D3”, 00 represents global over-current

protection, and 01 represents individual port over-current protection.

Figure 6 demonstrates a LQFP-64 implementation of Individual Mode design with dual-channel power

distribution switches. In this case, 3,3V pull-up are used for PWRJ/Enable pins to meet the requirement

of the specific switches used.

Figure 7 demonstrates LQFP-64 implementations of Multiple Gangs Mode and Ganged Mode with

Jul. 16, 2009

Subject to Change Without Notice

13

Fig. 6: LQFP-64 Individual Power Control Mode Example

5V

3.3V

To VBUS

of Port 4

To VBUS

of Port 3

To VBUS

of Port 2

To VBUS

of Port 1

FLGB

ENB

FLGA

ENA

OUTA

OUTB

IN

GND

MIC2026-2

PWRJ[7]

PWRJ[6]

PWRJ[5]

PWRJ[4]

PWRJ[3]

PWRJ[2]

PWRJ[1]

OVCJ[7]

OVCJ[6]

OVCJ[5]

OVCJ[4]

OVCJ[3]

OVCJ[2]

OVCJ[1]

FE2.1

FLGB

ENB

FLGA

ENA

OUTA

OUTB

IN

GND

MIC2026-2

FLGB

ENB

FLGA

ENA

OUTA

OUTB

IN

GND

MIC2026-2

FLGB

ENB

FLGA

ENA

OUTA

OUTB

IN

GND

MIC2026-2

To VBUS

of Port 5

To VBUS

of Port 6

To VBUS

of Port 7

3.3V