 (P srnsc“
(P srnsc“
 
 
 
 
 
 
 
 
 
 
 
±15kV ESD Protected MII/RMII 10/100 Ethernet Transceiver with HP Auto-MDIX Support and flexPWR®  Technology in a Small Footprint
Revision 2.3 (04-12-11) 8 SMSC LAN8700/LAN8700i
PRODUCT PREVIEW
RXD1/
MODE1
I/O Receive Data 1: Bit 1 of the 4 data bits that are sent by the PHY 
in the receive path.
PHY Operating Mode Bit 1: set the default MODE of the PHY. 
RXD2/
MODE2
I/O Receive Data 2: Bit 2 of the 4 data bits that are sent by the PHY 
in the receive path. 
PHY Operating Mode Bit 2: set the default MODE of the PHY. 
Notes:
RXD2 is not used in RMII Mode.
RXD3/
nINTSEL
I/O Receive Data 3: Bit 3 of the 4 data bits that are sent by the PHY 
in the receive path. 
nINTSEL: On power-up or external reset, the mode of the 
nINT/TXER/TXD4 pin is selected. 
When RXD3/nINTSEL is floated or pulled to VDDIO, nINT is 
selected for operation on pin nINT/TXER/TXD4 (default).
When RXD3/nINTSEL is pulled low to VSS through a resistor, 
TXER/TXD4 is selected for operation on pin nINT/TXER/TXD4.
Notes:
RXD3 is not used in RMII Mode
If the nINT/TXER/TXD4 pin is configured for nINT mode, then 
a pull-up resistor is needed to VDDIO on the nINT/TXER/TXD4 
pin.
RX_ER/
RXD4/
OReceive Error: Asserted to indicate that an error was detected 
somewhere in the frame presently being transferred from the 
PHY. 
MII Receive Data 4: In Symbol Interface (5B Decoding) mode, 
this signal is the MII Receive Data 4 signal, the MSB of the 
received 5-bit symbol code-group. Unless configured in this 
mode, the pin functions as RX_ER.
Note: This pin has an internal pull-down resistor, and must not 
be high during reset. The RX_ER signal is optional in 
RMII Mode.
RX_DV O Receive Data Valid: Indicates that recovered and decoded data 
nibbles are being presented on RXD[3:0]. 
Note: This pin has an internal pull-down resistor, and must not 
be high during reset. This signal is not used in RMII 
Mode.
RX_CLK/
REGOFF
I/O Receive Clock: In MII mode, this pin is the receive clock output. 
25MHz in 100Base-TX mode. 2.5MHz in 10Base-T mode.
Note: This signal is not used in RMII Mode.
Regulator Off: This pin may be used to configure the internal 
1.8V regulator off. This pin is sampled during the power-on 
sequence to determine if the internal regulator should turn on. 
When the regulator is disabled, external 1.8V must be supplied 
to VDD_CORE, and the voltage at VDD33 must be at least 
2.64V before voltage is applied to VDD_CORE.
Table 2 MII Signals (continued) 
SIGNAL NAME TYPE DESCRIPTION