Datasheet

KSZ8873MLL/FLL/RLL
DS00002348A-page 6  2017 Microchip Technology Inc.
TABLE 2-1: SIGNALS
Pin
Number
Pin
Name
Type
Note
2-1
Description
1 RXM1 I/O Physical receive or transmit signal (– differential)
2 RXP1 I/O Physical receive or transmit signal (+ differential)
3AGNDGND
Analog ground
4TXM1I/O
Physical transmit or receive signal (– differential)
5 TXP1 I/O
Physical transmit or receive signal (+ differential)
6 VDDA_3.3 P
3.3V analog V
DD
7AGNDGND
Analog ground
8 ISET O
Set physical transmit output current.
Pull-down this pin with an 11.8k 1% resistor to ground.
9 VDDA_1.8 P
1.8V analog core power input from VDDCO (pin 56).
10 RXM2 I/O Physical receive or transmit signal (– differential)
11 RXP2 I/O Physical receive or transmit signal (+ differential)
12 AGND GND Analog ground
13 TXM2 I/O Physical transmit or receive signal (– differential)
14 TXP2 I/O Physical transmit or receive signal (+ differential)
15 FXSD2 I
MLL/RLL: connect to analog ground by pull-down resistor.
FLL: Fiber signal detect/factory test pin
16 PWRDN Ipu
Chip power down input (active-low)
17 X1 I
25 MHz or 50 MHz crystal/oscillator clock connections.
Pins (X1, X2) connect to a crystal. If an oscillator is used, X1 connects to a
3.3V tolerant oscillator and X2 is a NC.
Note: Clock is ±50 ppm for both crystal and oscillator, the clock should be
applied to X1 pin before reset voltage goes high.
18 X2 O
19 SMTXEN3 Ipu Switch MII transmit enable
20
SMTXD33/
EN_REFCLKO_3
Ipu/I
MLL/FLL: Switch MII transmit data bit 3
RLL: Strap option: RMII mode Clock selection
PU = Enable REFCLKO_3 output
PD = Disable REFCLKO_3 output
21
SMTXD32/
NC
Ipu
MLL/FLL: Switch MII transmit data bit 2
RLL: No connection
22 SMTXD31 Ipu Switch MII/RMII transmit data bit 1
23 SMTXD30 Ipu Switch MII/RMII transmit data bit 0
24 GND GND Digital ground
25 VDDIO P
3.3V, 2.5V, or 1.8V digital V
DD
input power supply for IO with well decoupling
capacitors.