USB2228-NU-09 Standard Microsystems (SMSC), USB2228-NU-09 Datasheet - Page 14

• Manufacturer Part Number: USB2228-NU-09
• Manufacturer: Standard Microsystems (SMSC)

Specifications of USB2228-NU-09

• Lead Free Status / RoHS Status: Compliant

4th Generation USB 2.0 Flash Media Controller with Integrated Card Power FETs
Datasheet
SMSC USB2227/USB2228
VDD18PLL
SYMBOL
SD_nWP
VSSPLL
VDDA33
USBDM
MD[7:0]
USBDP
XTAL1/
ATEST
RBIAS
XTAL2
CLKIN
VSSA
128-PIN
VTQFP
101
104
102
103
25
87
88
98
99
89
86
12
10
11
9
8
7
6
5
BUFFER
I/O8PU
OCLKx
TYPE
ICLKx
IO-U
AIO
IPD
I
MEMORY/IO INTERFACE
USB INTERFACE
DATASHEET
SD Write Protected:
This pin is an input signal with an internal weak pull-down.
This pin has an internally controlled weak pull-down resistor.
USB Bus Data:
These pins connect to the USB bus data signals.
USB Transceiver Bias:
A 12.0kΩ, ± 1.0% resistor is attached from VSSA to this pin, in
order to set the transceiver’s internal bias currents.
Analog Test:
This signal is used for testing the analog section of the chip and
should be connected to VDDA33 for normal operation.
1.8v Power for the PLL
PLL Ground Reference:
Ground Reference for 1.8v PLL power
3.3v Analog Power
Analog Ground Reference:
Analog Ground Reference for 3.3v Analog Power.
Crystal Input/External Clock Input:
24Mhz Crystal or external clock input.
This pin can be connected to one terminal of the crystal or can
be connected to an external 24Mhz clock when a crystal is not
used.
Note:
Crystal Output:
24Mhz Crystal
This is the other terminal of the crystal, or left open when an
external clock source is used to drive XTAL1/CLKIN. It may not
be used to drive any external circuitry other than the crystal
circuit.
Memory Data Bus:
When ROMEN bit of GPIO_IN1 register = 0, these signals are
used to transfer data between the internal CPU and the external
program memory.
These pins have internally controlled weak pull-up resistors.
14
The MA[2:0] pins will be sampled while nRESET is
asserted, and the value will be latched upon nRESET
negation. This will determine the clock source and
value.
DESCRIPTION
Revision 1.93 (11-01-07)