USB2412-DZK Standard Microsystems (SMSC), USB2412-DZK Datasheet - Page 10

• Manufacturer Part Number: USB2412-DZK
• Manufacturer: Standard Microsystems (SMSC)

Specifications of USB2412-DZK

• Lead Free Status / RoHS Status: Supplier Unconfirmed

Revision 1.0 (02-12-10)
3.3
PIN
21
22
18
28
12
26
11
#
1
3
2
7
8
USBDM_DN[1]
USBDM_DN[2]
USBDP_DN[1]
USBDP_DN[2]
USBDM_UP
USBDP_UP
PRTPWR[1]
PRTPWR[2]
VBUS_DET
OCS_N[1]
OCS_N[2]
SYMBOL
Pin Descriptions (Grouped by Function)
RBIAS
BUFFER
TYPE
I/O12
IO-U
IO-U
IPD
IPU
I-R
DOWNSTREAM USB 2.0 INTERFACES
Table 3.2 USB2412 Pin Descriptions
UPSTREAM USB 2.0 INTERFACES
USB Bus Data
These pins connect to the upstream USB bus data signals (host, port,
or upstream hub).
Detect Upstream VBUS Power
Detects the state of Upstream VBUS power. The SMSC hub monitors
VBUS_DET to determine when to assert the internal D+ pull-up
resistor which signals a connect event.
When designing a detachable hub, this pin should be connected to
VBUS on the upstream port via a 2 to 1 voltage divider.
For self-powered applications with a permanently attached host, this
pin must be connected to 3.3 V.
According to Section 7.2.1 of the USB 2.0 specification, a downstream
port can never provide power to its D+ or D- pull-up resistors unless
the upstream port’s VBUS is in the asserted (powered) state.
The VBUS_DET pin on the hub monitors the state of the upstream
VBUS signal and will not pull-up the D+ resistor if VBUS is not active.
If VBUS goes from an active to an inactive state (Not Powered), the
hub will remove power from the D+ pull-up resistor within 10 seconds.
Hi-Speed USB Data
These pins connect to the downstream USB peripheral devices
attached to the hub’s ports.
USB Power Enable
Enables power to USB peripheral devices that are downstream. The
hub supports active high power controllers only.
Over-Current Sense
Input from external current monitor indicating an over-current
condition. This pin contains an internal pull-up to the 3.3 V supply.
USB Transceiver Bias
A 12.0 kΩ (+/- 1%) resistor is attached from ground to this pin to set
the transceiver’s internal bias settings.
DATASHEET
10
DESCRIPTION
2-Port USB 2.0 Hi-Speed Hub Controller
SMSC USB2412
Datasheet