Справочник Пользователя для SMSC USB2513B

USB 2.0 Hi-Speed Hub Controller

SMSC USB251x

27

Revision 1.0 (3-11-09)

SEL48

I

48 MHz Clock Input Selection

48 MHz external input clock select. When the hub is clocked from an external 

clock source, this pin selects either 24 MHz or 48 MHz mode.

‘0’ = 24 MHz

‘1’ = 48 MHz

CRFILT

VDD Core Regulator Filter Capacitor

This pin must have a 1.0 

μF (or greater) ±20% (ESR <0.1 

Ω

) capacitor to 

VSS.

VDD33

3.3 V Power 

PLLFILT

PLL Regulator Filter Capacitor

This pin must have a 1.0 

μF (or greater) ±20% (ESR <0.1 

Ω

) capacitor to 

VSS.

VSS

Ground Pad / ePad

The package slug is the only VSS for the device and must be tied to ground 

with multiple vias.

NC

No Connect

No signal or trace should be routed or attached to these pins.

I

Input.

I/O

Input/Output.

IPD

Input with internal weak pull-down resistor.

IPU

Input with internal weak pull-up resistor.

IS

Input with Schmitt trigger.

O12

Output 12 mA.