AX88772 datasheet(8/43 Pages) ASIX

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ASIX ELECTRONICS CORPORATION

AX88772

USB to 10/100 Fast Ethernet/HomePNA Controller

ET_SPEED_LED

Ethernet speed LED indicator. This pin drives low when the Ethernet

PHY is in 100BASE-TX mode and drives high when in 10BASE-T

mode.

Misc. Pins

RESET_N

I5/PU/S

Chip Reset Input. RESET_N pin is active low. When asserted, it puts

the entire chip into reset state immediately. After completing reset,

EEPROM data will be loaded automatically.

EXTWAKEUP_N I5/PU/S

Remote-wakeup trigger from external pin. EXTWAKEUP_N should

be asserted low for more than 2 cycles of 12MHz clock to be

effective. For

GPIO [2:0]

B5/PD

1, 2, 3

General Purpose Input/ Output Pins. These pins are default as input

pins after power-on reset. Please use GPIO0 for controlling the power

down pin of external Ethernet Phy, if applicable.

PHYRST_N

122

PHYRST_N is a tri-state output used for resetting external Ethernet

PHY. This pin is default in tri-state after power-on reset. If external

Ethernet PHY’s reset level is active low, connect this to PHY’s reset

pin with a pulled-down resistor. If it’s active high, connect this to

PHY with a pulled-up resistor. This way can make sure the external

Ethernet PHY stays in reset state before software brings it out of reset.

FORCEFS_N

I3/PU

Force USB Full Speed (active low). For normal operation, user should

keep this pin NC to enable USB High Speed handshaking process to

decide the speed of USB bus. Setting this pin low sets the device to

operate at Full speed mode only and disables Chirp K (HS

handshaking process).

LED

125

LED indicator: When USB bus is in Full speed, this pin drives high

continuously. When USB bus is in High speed, this pin drives low

continuously. This pin drives high and low in turn (blinking) to

indicate TX data transfer going on whenever the host controller sends

bulk out data transfer.

USB_SPEED_LE

126

USB bus speed LED indicator. When USB bus is in Full speed, this

pin drives high continuously. When USB bus is in High speed, this

pin drives low continuously.

TESTSPEEDUP

I3/PD