SMSC USB4640i Switch User Manual


 
High Speed Inter-Chip USB 2.0 Hub and Flash Media Controller
Datasheet
Revision 1.0 (06-01-09) 18 SMSC USB4640/USB4640i
DATASHEET
xD_nB/R 28 IPU xD-Picture Card Busy or Data Ready
This pin is connected to the BSY/RDY pin of the xD-Picture Card
device.
When using the internal FET, this pin has an internal weak pull-up
resistor that is tied to the output of the internal power FET.
If an external FET is used (the internal FET is disabled), then the
internal pull-up is not available (an external pull-up is required).
xD_nCE 26 O8PU xD-Picture Card Chip Enable
This pin is an active low chip enable signal for the xD-Picture Card
device.
When using the internal FET, this pin has an internal weak pull-up
resistor that is tied to the output of the internal power FET.
If an external FET is used (internal FET is disabled), then the internal
pull-up is not available (an external pull-up is required).
xD_CLE 24 O8PD xD-Picture Card Command Strobe
This pin is an active high Command Latch Enable signal for the xD-
Picture Card device. This pin has a weak pull-down resistor that is
permanently enabled.
GPIO14 /
xD_nCD
29 I/O6 This general purpose pin may be used either as input, edge sensitive
interrupt input, or output. Custom firmware is required to activate this
function.
I/O8 xD-Picture Card Detection GPIO
This is a GPIO designated by the default firmware as the xD-Picture
Card detection pin and has an internal pull-up.
xD_nRE 27 O8PU xD-Picture Card Read Enable
This pin is an active low read strobe signal for the xD-Picture Card
device.
When using the internal FET, this pin has an internal weak pull-up
resistor that is tied to the output of the internal power FET.
If an external FET is used (internal FET is disabled), then the internal
pull-up is not available (an external pull-up is required).
xD_nWE 22 O8PU xD-Picture Card Write Enable
This pin is an active low write strobe signal for the xD-Picture Card
device.
When using the internal FET, this pin has an internal weak pull-up
resistor that is tied to the output of the internal power FET.
If an external FET is used (internal FET is disabled), then the internal
pull-up is not available (an external pull-up is required).
Table 6.1 USB4640/USB4640i Pin Descriptions (continued)
SYMBOL
48-PIN
QFN
BUFFER
TYPE
(Table 6.2)DESCRIPTION