Datasheet

6-MHz Clock
Signal
DP1
DM1
DP2
DM2
PWRON1
PWRON7
OVRCUR1
OVRCUR7
GND
XTAL1
XTAL2
EXTMEM
RESET
TPS2044
IN1EN1
OUT1
D +
D -
5 V
GND
D +
D -
5 V
Downstream
Ports
OC1
TUSB2077A
DP6
DM6
DP7
DM7
SN75240
A
B
C
D
100 mF
GND
100 mF
DP0
DM0
V
CC
5 V
3.3 V
GND
D +
D -
Upstream
Port
3.3 V LDO
§
SN75240
A
B
5 V
GND
C
D
4.7 mF
0.1 mF
4.7 mF
Ferrite Beads
5 V Board Power
Supply
Ferrite Beads
0.1 mF
D +
D -
5 V
GND
D +
D -
5 V
GND
100 mF
Ferrite Beads
SN75240
A
B
C
D
100 mF
BUSPWR
3.3 V
Ferrite Beads
EEDATA/GANGED
System
Power-On Reset
EN2
EN3
EN4
OC2
OC3
OC4
OUT2
OUT3
OUT4
IN2
1.5 k
3.3 V
15 k
15 k
15 k
15 k
15 k
15 k
15 k
15 k
MODE
DP0PUR
NOTES:
LDO is a 5-V-to-3.3-V voltage regulator. TPS76333 from Texas Instruments can be used.
All USB DP, DM signal pairs require series resistors of approximately 27
TPS2044, TPS2042, and SN75240 are Texas Instruments devices. The TPS2024 can be substituted for the TPS2044.
120 µF per hub is the minimum required per the USB specification. However, TI recommends a 100-µF, low ESR,
tantalum capacitor per port for immunity to voltage droop.
§
to ensure proper termination. An optional filter
capacitor of about 22 pF is recommended for EMI suppression. This capacitor, if used, must be placed between the hub
terminal and the series resistor, as per section 7.1.6 of the USB specification.
TUSB2077A
SLLS414E MARCH 2000REVISED SEPTEMBER 2013
www.ti.com
Self-Powered Hub, Ganged-Port Power Management
The TUSB2077A can also be implemented for ganged-port power management in a self-powered configuration.
The implementation is very similar to the bus-powered example with the exception that a self-powered port
supplies 500 mA of current to each downstream port. The overcurrent protection can be provided by a TPS2044
quad device or a TPS2024 single power switch.
Figure 11. TUSB2077A Self-Powered Hub, Ganged-Port Power-Management Application
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