
LXT9785 and LXT9785E Advanced 8-Port 10/100 Mbps PHY Transceivers
176
Datasheet
Document Number: 249241
Revision Number: 010
Revision Date: 30-May-2006
Table 57. 100BASE-TX Transceiver Characteristics
Parameter
Sym
Min
Typ
1
Max
Units
Test Conditions
Peak differential output
voltage
VP
0.95
–
1.05
V
Note 2
Signal amplitude symmetry
Vss
98
–
102
%
Note 2
Signal rise/fall time
trf
3–
5
ns
Note 2
Rise/fall time symmetry
trfs
–
0.5
ns
Note 2
Duty cycle distortion
–
+/- 0.5
ns
Offset from 16 ns pulse
width at 50% of pulse
peak
Overshoot
VO
––
5
%
–
Jitter magnitude (measured
differentially)
ttx-jit
––
1.4
ns
–
1. Typical values are at 25 °C and are for design aid only; not guaranteed and not subject to production
testing.
2. Measured at the line side of the transformer, line replaced by 100
Ω (+/-1%) resistor.
Table 58. 100BASE-FX Transceiver Characteristics
Parameter
Sym
Min
Typ
1
Max
Units
Test Conditions
Transmitter
Peak-to-peak differential
output voltage
V
DIFFP
-P
0.6
1.44
–
V
–
Signal rise/fall time
trf
–
1.8
ns
Note 2
Jitter magnitude (measured
differentially)
ttx-jit
––
1.4
ns
–
Receiver
Peak differential input
voltage
VIP
0.55
–
V
–
Common mode input range
VCMIR
––
VCC - 0.5
V
–
Input Low Voltage (SD pins)
VIL
VCC
-1.84
VCC
-1.63
V–
Input High Voltage (SD Pins)
VIH
VCC
-1.04
VCC
-0.88
V–
1. Typical values are at 25 °C and are for design aid only; not guaranteed and not subject to production
testing.
2. 20 - 80 percent into 100
Ω equivalent load of a typical fiber transceiver.