4th Generation USB 2.0 Flash Media Controller with Integrated Card Power FETs

Datasheet

Revision 1.4 (10-08-07)

14

SMSC USB2226

DATASHEET

USB INTERFACE

USBDM

USBDP

87

88

I/O-U

USB Bus Data:

These pins connect to the USB bus data signals.

RBIAS

98

I

USB Transceiver Bias:

A 12.0k

Ω, ± 1.0% resistor is attached from VSSA to this pin, in order

to set the transceiver’s internal bias currents.

ATEST

99

AIO

Analog Test:

This signal is used for testing the analog section of the chip and

should be connected to VDDA33 for normal operation.

VDD18PLL

101

1.8v Power for the PLL

VSSPLL

104

PLL Ground Reference:

Ground Reference for 1.8v PLL power

VDDA33

89

3.3v Analog Power

VSSA

86

Analog Ground Reference:

Analog Ground Reference for 3.3v Analog Power.

XTAL1/

CLKIN

102

ICLKx

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:

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.

XTAL2

103

OCLKx

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.

MISC

ACT_LED

114

I/O8

Media Activity LED:

This active low output will blink if any media is accessed by the USB

host.

VBUS

94

I/O8

VBUS Input:

This pin should be connected to the USB bus VBUS signal through

a 100K

Ω resistor voltage divider to provide 2.5v when VBUS = 5.0v.

SD_nCD

110

I/O8

SD Card Detection:

This is the card detection signal from SD socket to indicate if the

device is inserted.

This pin has an internally controlled weak pull-up resistor.

MS_PWR

42

I/O8

MS Card Power drive of 3.3V @ 100mA.

SYMBOL

128-PIN

VTQFP

BUFFER

TYPE

DESCRIPTION