LAN9215I_07 Datasheet, PDF (136/138 Pages) SMSC Corporation – Highly Efficient Single-Chip 10/100 Ethernet Controller with HP Auto-MDIX and Industrial Temperature Support

Highly Efficient Single-Chip 10/100 Ethernet Controller with HP Auto-MDIX and Industrial Temperature Support
Datasheet
Table 7.6 10BASE-T Transceiver Characteristics
PARAMETER
SYMBOL MIN
TYP MAX UNITS
Transmitter Peak Differential
Output Voltage
Receiver Differential Squelch
Threshold
V_OUT
2.2
2.5
2.8
V
V_DS
300
420
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 LAN9215i can accept either a 25MHz crystal (preferred) or a 25 MHz single-ended clock oscillator
(±50 PPM) input. The LAN9215i 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 LAN9215i
crystal input/output signals (XTAL1, XTAL2). See Table 7.7, "LAN9215i Crystal Specifications" for
crystal specifications. Refer to application note AN10.7 - “Parallel Crystal Circuit Input Voltage Control”
for additional information.
Table 7.7 LAN9215i 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
LAN9215i XTAL1/CLKIN Pin
Capacitance
LAN9215i 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
-40
-
+85
-
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
Revision 1.93 (12-12-07)
136
DATASHEET
SMSC LAN9215i