LAN9514I-JZX SMSC, LAN9514I-JZX Datasheet - Page 16

• Manufacturer Part Number: LAN9514I-JZX
• Description: Ethernet ICs Hi-Speed USB 2.0 Hub High Perf 10/100 Ind
• Manufacturer: SMSC

Specifications of LAN9514I-JZX

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Revision 1.0 (11-24-09)
2.1
2.1.1
USB Power
USB Power
Port Power Control
Device
Switch
Device
Switch
5V
5V
USB
USB
This section details the usage of the port power control pins PRTCTL[5:2].
Port Power Control Using a USB Power Switch
The LAN9514/LAN9514i has a single port power control and over-current sense signal for each
downstream port. When disabling port power the driver will actively drive a ‘0’. To avoid unnecessary
power dissipation, the internal pull-up resistor will be disabled at that time. When port power is enabled,
the output driver is disabled and the pull-up resistor is enabled, creating an open drain output. If there
is an over-current situation, the USB Power Switch will assert the open drain OCS signal. The schmitt
trigger input will recognize this situation as a low. The open drain output does not interfere. The
overcurrent sense filter handles the transient conditions, such as low voltage, while the device is
powering up.
OCS
OCS
EN
EN
Figure 2.2 Port Power Control with USB Power Switch
PRTCTL4
PRTCTL5
DATASHEET
LAN9514/
LAN9514i
16
PRTCTL3
PRTCTL2
USB 2.0 Hub and 10/100 Ethernet Controller
EN
EN
OCS
OCS
SMSC LAN9514/LAN9514i
USB Power
USB Power
Switch
Switch
Device
Device
USB
USB
5V
5V
Datasheet