High Speed Inter-Chip USB 2.0 Hub and Flash Media Controller

 

 

 

Datasheet

 

Table 6.1 USB4640/USB4640i Pin Descriptions (continued)

 

 

 

 

 

48-PIN

BUFFER

 

 

QFN

TYPE

 

SYMBOL

 

(Table 6.2)

DESCRIPTION

 

 

 

 

GPIO2 /

36

I/O6

This pin may be used either as input, edge sensitive interrupt input,

 

 

 

or output. Custom firmware is required to activate this function.

 

 

 

 

RXD

 

 

This signal can be configured as input to the RXD of the internal

 

 

 

UART. Custom firmware is required to activate this function.

 

 

 

 

GPIO10

35

I/O200

Card power drive: 3.3 V (100 mA or 200 mA)

(CRD_PWR)

 

 

This must be the only FET used to power devices. Failure to do this

 

 

 

 

 

 

will violate voltage specifications on device pins. If this pin is not

 

 

 

being used as a card power pin, this pin may be used either as input,

 

 

 

edge sensitive interrupt input, or output (GPIO).

 

 

 

Please see Section 8.4.2.3, "A4h-A5h: Smart Media Device Power

 

 

 

Configuration," on page 38 for more information.

 

 

 

 

nRESET

38

IS

RESET input

 

 

 

The system uses this active low signal to reset the chip. The active

 

 

 

low pulse should be at least 1 μs wide.

 

 

 

 

TEST

40

I

TEST Input

 

 

 

Tie this pin to ground for normal operation.

 

 

 

 

 

 

DIGITAL / POWER / GROUND

 

 

 

 

CRFILT

15

 

VDD Core Regulator Filter Capacitor

 

 

 

This pin requires a 1.0 μF (or greater) ± 20% (ESR <0.1Ω) capacitor

 

 

 

to VSS.

 

 

 

 

PLLFILT

46

 

Phase-locked Loop Regulator Filter Capacitor

 

 

 

This pin requires a 1.0 μF (or greater) ± 20% (ESR <0.1Ω) capacitor

 

 

 

to VSS.

 

 

 

 

VDD12

41

 

1.2 V Power for HSIC pads and buffers

 

 

 

 

VDD33

5

 

3.3 V Power and Regulator Input

 

12

 

 

 

16

 

Please see Chapter 10, "DC Parameters," on page 56 for more

 

25

 

information.

 

34

 

Pins 16 and 48 each require an external bypass capacitor of 4.7 μF

 

48

 

 

 

 

minimum.

 

 

 

 

VSS

ePad

 

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

 

 

 

ground with multiple vias.

 

 

 

 

Revision 1.0 (06-01-09)

20

SMSC USB4640/USB4640i

DATASHEET