SMSC USB2250i User Manual
Page 13
Ultra Fast USB 2.0 Multi-Slot Flash Media Controller
Datasheet
SMSC USB2250/50i/51/51i
13
Revision 1.1 (05-29-08)
DATASHEET
SM Address
Strobe
SM_ALE
52
O12PD
This pin is an active high Address Latch
Enable signal for the SM device.
This pin has a weak pull-down resistor that
is permanently enabled.
SM Command
Strobe
SM_CLE
53
O12PD
This pin is an active high Command Latch
Enable signal for the SM device.
This pin has a weak pull-down resistor that
is permanently enabled.
SM Data 7-0
SM_D[7:0]
39
40
41
42
43
44
45
46
I/O12PD
These pins are the bi-directional data signals
SM_D7-SM_D0.
The bi-directional data signal has an internal
weak pull-down resistor.
SM Read Enable
SM_nRE
55
O12PU
This pin is an active low read strobe signal
for the SM 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, and is
controlled by the SM_PU bit of the
SMC_CTL register.
If an external FET is used (Internal FET is
disabled), then the internal pull-up is not
available (external pull-ups must be used).
SM Write Enable
SM_nWE
48
O12PU
This pin is an active low write strobe signal
for SM 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, and is
controlled by the SM_PU bit of the
SMC_CTL register.
If an external FET is used (Internal FET is
disabled), then the internal pull-up is not
available (external pull-ups must be used).
SM Write Protect
Switch
SM_nWPS
38
IPU
A write-protect seal is detected when this pin
is low.
This pin has an internal weak pull-up resistor
that is controlled by the SM_INTF_EN bit of
the SMC_MODE_CTL2 register.
Table 5.1 USB2250/50i/51/51i 128-Pin VTQFP Pin Descriptions (continued)
NAME
SYMBOL
128-PIN
VTQFP
BUFFER
TYPE
DESCRIPTION