LM3S8938 Datasheet, PDF (589/621 Pages) List of Unclassifed Manufacturers – Microcontroller

Stellaris® LM3S8938 Microcontroller
Table 22-25. 10BASE-T Transmitter Characteristics (continued)
Parameter Name
Start-of-idle pulse width
Min
Nom
Max
Unit
-
300
-
ns
350
a. The Manchester-encoded data pulses, the link pulse and the start-of-idle pulse are tested against the templates and using
the procedures found in Clause 14 of IEEE 802.3.
Table 22-26. 10BASE-T Transmitter Characteristics (informative)^a
Parameter Name
Min
Nom
Max
Unit
Output return loss
15
-
-
dB
Output impedance balance
29-17log(f/10)
-
-
dB
Peak common-mode output voltage
-
-
50
mV
Common-mode rejection
-
-
100
mV
Common-mode rejection jitter
-
-
1
ns
a. The specifications in this table are included for information only. They are mainly a function of the external transformer
and termination resistors used for measurements.
Table 22-27. 10BASE-T Receiver Characteristics
Parameter Name
DLL phase acquisition time
Jitter tolerance (pk-pk)
Input squelched threshold
Input unsquelched threshold
Differential input resistance
Bit error ratio
Common-mode rejection
Min
Nom
Max
Unit
-
10
-
BT
30
-
-
ns
500
600
700
mVppd
275
350
425
mVppd
-
20
-
kΩ
-
10^-10
-
-
25
-
-
V
Table 22-28. 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.
June 22, 2010
589
Texas Instruments-Production Data