LAN9217_07 Datasheet, PDF (135/137 Pages) SMSC Corporation – 16-bit High-Performance Single-Chip 10/100 Ethernet Controller with HP Auto-MDIX

16-bit High-Performance Single-Chip 10/100 Ethernet Controller with HP Auto-MDIX
Datasheet
Table 7.6 10BASE-T Transceiver Characteristics
PARAMETER
Transmitter Peak Differential
Output Voltage
Receiver Differential Squelch
Threshold
SYMBOL MIN
V_OUT
2.2
V_DS
300
TYP
2.5
420
MAX
2.8
UNITS
V
585
mV
NOTES
Note 7.11
Note 7.11 Measured at the line side of the transformer, line replaced by 100Ω (+/- 1%) resistor.
7.6
Clock Circuit
The LAN9217 can accept either a 25MHz crystal (preferred) or a 25 MHz single-ended clock oscillator
(±50 PPM) input. The LAN9217 shares the 25MHz clock oscillator input (CLKIN) with the crystal input
XTAL1/CLKIN (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 LAN9217
crystal input/output signals (XTAL1, XTAL2). See Table 7.7, "LAN9217 Crystal Specifications" for
crystal specifications. Refer to application note AN10.7 - “Parallel Crystal Circuit Input Voltage Control”
for additional information.
Table 7.7 LAN9217 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
LAN9217 XTAL1/CLKIN Pin
Capacitance
LAN9217 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 7.12
Note 7.12
Note 7.13
Note 7.14
Note 7.15
pF
Note 7.15
Note 7.12
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 LAN9217
135
DATASHEET
Revision 1.8 (06-06-07)