AC characteristic

A simplified AC model of the transmission circuits

is shown in figure 15.

Where :

is the received signal

is the transmitted signal

is the AC transversal voltage at line terminations.

is the line open circuit AC voltage

is the line impedance

are the protection resistors

is the line impedance balancing network

is the SLIC impedance balancing network

program the AC line termination impedance

used for external protection resistors insertion

loss compensation

is the AC transversal current divided by 50

CAC AC feedback current decoupling

Figure 13: DC characteristic in Active Mode with two different values of limiting current (30mA and 70 mA).

Figure 14: Line current versus loop resistance with two different values of limiting current (30mA and

70mA)

L3234 - L3235

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