4th Generation USB2.0 Flash Media Controller with Integrated Card Power FETs

Datasheet

Revision 1.77 (06-13-05)

20

SMSC USB2227/USB2228

DATASHEET

Notes:

■

Hot-insertion capable card connectors are required for all flash media. It is required for SD

connector to have Write Protect switch. This allows the chip to detect MMC card.

■

nMCE is normally asserted except when the 8051 is in standby mode.

6.2

Buffer Type Descriptions

3.3v Power & &

Voltage Regulator

Input

VDD33

3.3V Power & Regulator Input.

pins 100 & 108 supply 3.3V power to the internal 1.8V

regulators.

Ground

VSS

Ground Reference

Table 6.1 USB2227/USB2228 Buffer Type Descriptions

BUFFER

DESCRIPTION

I

Input

IPU

Input with internal weak pull-up resistor.

IPD

Input with internal weak pull-down resistor.

IS

Input with Schmitt trigger

I/O8

Input/Output buffer with 8mA sink and 8mA source.

I/O8PU

Input/Output buffer with 8mA sink and 8mA source, with an internal weak pull-up resistor.

I/O8PD

Input/Output buffer with 8mA sink and 8mA source, with an internal weak pull-down

resistor.

O8

Output buffer with 8mA sink and 8mA source.

O8PU

Output buffer with 8mA sink and 8mA source, with an internal weak pull-up resistor.

O8PD

Output buffer with 8mA sink and 8mA source, with an internal weak pull-down resistor.

ICLKx

XTAL clock input

OCLKx

XTAL clock output

I/O-U

Analog Input/Output Defined in USB specification

AIO

Analog Input/Output

NAME

SYMBOL

BUFFER

TYPE

DESCRIPTION