LM3S6422 Datasheet, PDF (573/609 Pages) Texas Instruments – Stellaris® LM3S6422 Microcontroller

Stellaris^® LM3S6422 Microcontroller
Table 18-25. 10BASE-T Receiver Characteristics
Parameter Name
Jitter tolerance (pk-pk)
Input squelched threshold
Differential input resistance
Common-mode rejection
Min
Nom
Max
30
-
-
500
600
700
-
20
-
25
-
-
Unit
ns
mVppd
kΩ
V
Table 18-26. Isolation Transformers^a
Name
Value
Condition
Turns ratio
1 CT : 1 CT
+/- 5%
Open-circuit inductance
350 uH (min)
@ 10 mV, 10 kHz
Leakage inductance
0.40 uH (max)
@ 1 MHz (min)
Inter-winding capacitance
25 pF (max)
DC resistance
0.9 Ohm (max)
Insertion loss
0.4 dB (typ)
0-65 MHz
HIPOT
1500
Vrms
a. Two simple 1:1 isolation transformers are required at the line interface. Transformers with integrated common-mode
chokes are recommended for exceeding FCC requirements. This table gives the recommended line transformer
characteristics.
Note:
The 100Base-TX amplitude specifications assume a transformer loss of 0.4 dB. For the
transmit line transformer with higher insertion losses, up to 1.2 dB of insertion loss can be
compensated by selecting the appropriate setting in the Transmit Amplitude Selection (TXO)
bits in the MR19 register.
Table 18-27. Ethernet Reference Crystal^a
Name
Value
Frequency
25.00000
Frequency tolerance
±50
Aging
±2
Temperature stability (-40° to 85°)
±5
Oscillation mode
Parallel resonance, fundamental mode
Parameters at 25° C ±2° C; Drive level = 0.5 mW
Drive level (typ)
50-100
Shunt capacitance (max)
10
Motional capacitance (min)
10
Series resistance (max)
60
Spurious response (max)
> 5 dB below main within 500 kHz
a. If the internal crystal oscillator is used, select a crystal that meets these specifications.
Condition
MHz
PPM
PPM/yr
PPM
µW
pF
fF
Ω
June 18, 2012
573
Texas Instruments-Production Data