Datasheet

78Q2120C
10/100BASE-TX
Transceiver
Page: 29 of 35 © 2009 Teridian Semiconductor Corporation Rev 1.3
10BASE-T Transmitter (Informative)
The specifications in the following table are included for information only. They are mainly a function of the
external transformer and termination resistors used for measurements.
PARAMETER CONDITION MIN NOM MAX UNIT
Output return loss 15 dB
Output Impedance Balance 1 MHz < freq < 20 MHz
29 17
10
−






log
f
dB
Peak Common-mode Output Voltage 50 mV
Common-mode rejection
15 V
pk
, 10.1 MHz sine
wave applied to
transmitter common-
mode. All data
sequences.
100 mV
Common-mode rejection jitter
15 V
pk
, 10.1 MHz sine
wave applied to
transmitter common-
mode. All data
sequences.
1 ns
10BASE-T Receiver
PARAMETER CONDITION MIN NOM MAX UNIT
DLL Phase Acquisition Time 10 BT
Jitter Tolerance (pk-pk) 30 ns
Input Squelched Threshold 500 600 700 mVppd
Input Unsquelched Threshold 275 350 425 mVppd
Differential Input Resistance 20
kΩ
Bit Error Ratio
10
-10
Common-mode rejection
Square wave
0 < f < 500 kHz
Not tested
25 V