Datasheet

LAN8700/LAN8700i
DS00002260A-page 12  2007-2016 Microchip Technology Inc.
TABLE 3-5: GENERAL SIGNALS
Signal Name Type Description
nINT/
TX_ER/
TXD4
IOPU LAN Interrupt – Active Low output. Place an external resistor (see
Table 4-3, “Boot Strapping Configuration Resistors,” on page 25)
pull-up to VCC 3.3V.
• This signal is mux’d with TXER/TXD4
• See Section 4.10, "nINT/TX_ER/TXD4 Strapping," on page 24
for additional details on Strapping options.
nRST I External Reset – input of the system reset. This signal is active
LOW. When this pin is deasserted, the mode register bits are
loaded from the mode pins as described in Section 5.4.9.2.
CLKIN/
XTAL1
I/O Clock Input – 25 Mhz or 50 MHz external clock or crystal input.
• In MII mode, this signal is the 25 MHz reference input clock
• In RMII mode, this signal is the 50 MHz reference input clock
which is typically also driven to the RMII compliant Ethernet
MAC clock input.
Note: See Section 4.10, "nINT/TX_ER/TXD4 Strapping," on
page 24 for additional details on Strapping options.
XTAL2 O Clock Output – 25 MHz crystal output.
Note: Float this pin if using an external clock being driven
through CLKIN/XTAL1
TABLE 3-6: 10/100 LINE INTERFACE
Signal Name Type Description
TXP AO Transmit Data Positive: 100Base-TX or 10Base-T differential
transmit outputs to magnetics.
TXN AO Transmit Data Negative: 100Base-TX or 10Base-T differential
transmit outputs to magnetics.
RXP AI Receive Data Positive: 100Base-TX or 10Base-T differential
receive inputs from magnetics.
RXN AI Receive Data Negative: 100Base-TX or 10Base-T differential
receive inputs from magnetics.
TABLE 3-7: ANALOG REFERENCES
Signal Name Type Description
EXRES1 AI Connects to reference resistor of value 12.4K-Ohm, 1% connected
as described in the Analog Layout Guidelines. The nominal
voltage is 1.2V and therefore the resistor will dissipate
approximately 1mW of power.