USB2504 SMSC Corporation, USB2504 Datasheet - Page 14

• Manufacturer Part Number: USB2504
• Description: Integrated USB 2.0 Compatible 4-Port Hub
• Manufacturer: SMSC Corporation

Revision 2.1 (12-06-06)
VDDAPLL3P3
VDDAPLL1P8
RESET Input
Internal 1.8V
Self-Power /
Analog Test
Bus-Power
TEST Pins
VDDIO3P3
VDDA3P3
regulator
VDD1P8
voltage
NAME
enable
NAME
Detect
VSS
&
VDDA33PLL
VDDA18PLL
SELF_PWR
RESET_N
TEST[1:0]
SYMBOL
SYMBOL
REG_EN
VDDA33
ATEST/
VDD18
VDD33
VSS
Table 4.4 Power, Ground, and No Connect
Table 4.3 Miscellaneous Pins (continued)
TYPE
TYPE
AIO
IPD
IS
I
DATASHEET
14
This active low signal is used by the system to reset the
chip. The minimum active low pulse is 1us.
Detects availability of local self-power source.
Low = Self/local power source is NOT available (i.e., Hub
gets all power from Upstream USB VBus).
High = Self/local power source is available.
Used for testing the chip. User must treat as a no-
connect or connect to ground.
This signal is used for testing the analog section of the
chip, and to enable or disable the internal 1.8v regulator.
This pin must be connected to VDDA33 to enable the
internal 1.8V regulator, or to VSS to disable the internal
regulator.
When the internal regulator is enabled, the 1.8V power
pins must be left unconnected, except for the required
bypass capacitors.When the PHY is in test mode, the
internal regulator is disabled and the ATEST pin
functions as a test pin.
+1.8V core power.
If the internal regulator is enabled, then VDD18 pin 54
must have a 4.7
capacitor to VSS
+3.3V Filtered analog power for the internal PLL
If the internal PLL 1.8V regulator is enabled, then this pin
acts as the regulator input
+1.8V Filtered analog power for internal PLL.
If the internal regulator is enabled, then this pin must
have a 4.7
to VSS
+3.3V I/O power.
+3.3V Filtered analog power.
Ground.
μ
F (or greater) ±20% (ESR <0.1
μ
F (or greater) ±20% (ESR <0.1
Integrated USB 2.0 Compatible 4-Port Hub
FUNCTION
FUNCTION
SMSC USB2504/USB2504A
Ω)
capacitor
Datasheet
Ω)