LAN9118_07 Datasheet, PDF (127/129 Pages) SMSC Corporation – High Performance Single-Chip 10/100 Non-PCI Ethernet Controller

High Performance Single-Chip 10/100 Non-PCI Ethernet Controller
Datasheet
Table 7.5 10BASE-T Tranceiver Characteristics
PARAMETER
Transmitter Peak Differential
Output Voltage
Receiver Differential Squelch
Threshold
SYMBOL MIN
V_OUT
2.2
V_DS
300
TYP MAX UNITS
2.5
2.8
V
420
585
mV
NOTES
Note 7.12
Note 7.12 Measured at the line side of the transformer, line replaced by 100Ω (+/- 1%) resistor.
7.6
Clock Circuit
The LAN9118 can accept either a 25MHz crystal (preferred) or a 25 MHz clock oscillator (±50 PPM)
input. The LAN9118 shares the 25MHz clock oscillator input (CLKIN) with the crystal input XTAL1 (pin
6). If the single-ended clock oscillator method is implemented, XTAL2 should be left unconnected and
CLKIN should be driven with a nominal 0-3.3V clock signal. The input clock duty cycle is 40%
minimum, 50% typical and 60% maximum.
It is recommended that a crystal utilizing matching parallel load capacitors be used for the LAN9118
crystal input/output signals (XTAL1, XTAL2). See Table 7.6, "LAN9118 Crystal Specifications" for crystal
specifications. Refer to SMSC Application Note AN10.7 - “Parallel Crystal Circuit Input Voltage Control”
and the LAN9118 Reference Schematic for additional information.
Table 7.6 LAN9118 Crystal Specifications
PARAMETER
Crystal Cut
Crystal Oscillation Mode
Crystal Calibration Mode
Frequency
Frequency Tolerance @ 25^oC
Frequency Stability Over Temp
Frequency Deviation Over Time
Total Allowable PPM Budget
Shunt Capacitance
Load Capacitance
Drive Level
Equivalent Series Resistance
Operating Temperature Range
LAN9118 XTAL1 Pin
Capacitance
LAN9118 XTAL2 Pin
Capacitance
SYMBOL
F_fund
F_tol
F_temp
F_age
C_O
C_L
P_W
R₁
MIN
NOM
MAX
AT, typ
Fundamental Mode
Parallel Resonant Mode
-
25.000
-
-
-
+/-50
-
-
+/-50
-
+/-3 to 5
-
-
-
+/-50
-
7 typ
-
-
20 typ
-
0.5
-
-
-
-
30
0
-
+70
-
3 typ
-
-
3 typ
-
UNITS NOTES
MHz
PPM
PPM
PPM
PPM
pF
pF
mW
Ohm
o_C
pF
Note 7.13
Note 7.13
Note 7.14
Note 7.15
Note 7.16
pF
Note 7.16
Note 7.13
The maximum allowable values for Frequency Tolerance and Frequency Stability are
application dependant. Since any particular application must meet the IEEE +/-50 PPM
Total PPM Budget, the combination of these two values must be approximately +/-45 PPM
(allowing for aging).
SMSC LAN9118
127
DATASHEET
Revision 1.3 (05-31-07)