USB2504A-JT Standard Microsystems (SMSC), USB2504A-JT Datasheet - Page 12

• Manufacturer Part Number: USB2504A-JT
• Manufacturer: Standard Microsystems (SMSC)

Specifications of USB2504A-JT

• Operating Temperature (min): 0C
• Operating Temperature Classification: Commercial
• Operating Temperature (max): 70C
• Package Type: TQFP
• Rad Hardened: No
• Lead Free Status / RoHS Status: Compliant

Revision 2.3 (08-27-07)
Polarity strapping.
USB Transceiver
strapping option.
Current Sensing
strapping option
Switching and
Port 4 Amber
Port 3 Amber
Port 2 Amber
Port 1 Amber
Over Current
MTT Disable
Gang Power
LED Enable
Port Power
NAME
Sense
LED
LED
LED
LED
Bias
&
&
&
PRTPWR_POL
OCS[4:1]_N
GANG_EN
SYMBOL
MTT_EN
LED_EN
RBIAS
AM4/
AM2/
AM1/
AM3
Table 4.1 4-Port Hub Pin Descriptions (continued)
TYPE
I/O12
I/O12
I/O12
I/O12
I/O12
IPU
I-R
DATASHEET
Amber indicator LED for port 4. Will be active low when LED
support is enabled via EEPROM or SMBus.
If the hub is configured by the internal default configuration,
this pin will be sampled at RESET_N negation to determine
if LED support is enabled or disabled. Also, the active state
of the LED will be determined as follows:
‘0’ = LED support is disabled, LED is inactive
‘1’ = LED Support is enabled, LED is active low.
Amber indicator LED for port 3. Signal will be active low.
Amber indicator LED for port 2. Will be active low when LED
support is enabled via EEPROM or SMBus.
If the hub is configured by the internal default configuration,
this pin will be sampled at RESET_N negation to determine
if MTT support is disabled (STT only). Also, the active state
of the LED will be determined as follows:
‘0’ = MTT support is disabled, LED is active high
‘1’ = MTT support is enabled, LED is active low.
Amber indicator LED for port 1, Will be active low when LED
support is enabled via EEPROM or SMBus.
If the hub is configured by the internal default configuration,
this pin will be sampled at RESET_N negation to determine
if downstream port power switching and current sensing are
ganged, or individual port-by-port. Also, the active state of
the LED will be determined as follows:
‘0’ = Port-by-port sensing & switching, LED is active high
‘1’ = Ganged sensing & switching, LED is active low.
Port Power Polarity strapping determination for the active
signal polarity of the [4:1]PRTPWR pins.
While RESET_N is asserted, the logic state of this pin will
(though the use of internal combinatorial logic) determine
the active state of the [4:1]PRTPWR pins in order to ensure
that downstream port power is not inadvertently enabled to
inactive ports during a hardware reset.
On the rising edge of RESET_N (see the applicable
RESET_N timing table in
be latched internally, and will retain the active signal polarity
for the PRTPWR[4:1] pins.
‘1’ = PRTPWR[4:1]_P/N pins have an active ‘high’ polarity
‘0’ = PRTPWR[4:1]_P/N pins have an active ‘low’ polarity
Input from external current monitor indicating an over-
current condition. {Note: Contains internal pull-up to 3.3V
supply}
A 12.0kΩ (+/− 1%) resistor is attached from ground to this
pin to set the transceiver’s internal bias settings.
12
Integrated USB 2.0 Compatible 4-Port Hub
FUNCTION
Section
5.6.1), the logic value will
SMSC USB2504/USB2504A
Datasheet