STLC3065 datasheet(12/27 Pages) STMICROELECTRONICS

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External Components List

In order to properly define the external compo-

nents value the following system parameters

have to be defined:

The AC input impedance shown by the SLIC at

the line terminals ”Zs” to which the return loss

measurement is referred. It can be real (typ.

600

Ω) or complex.

The AC balance impedance, it is the equiva-

lent impedance of the line ”Zl” used for evalu-

ation of the trans-hybrid loss performances

(2/4 wire conversion). It is usually a complex

impedance.

The value of the two protection resistors Rp in

series with the line termination.

The line impedance at the TTX frequency

”Zlttx”.

The metering pulse level amplitude measured

at line termination ”VLOTTX”. In case of low or-

der filtering, VLOTTX represents the amplitude

(Vrms) of the fundamental frequency compo-

nent. (typ 12 or 16KHz).

Pulse metering envelope rise and decay time

constant ”t”.

The slope of the ringing waveform ”

∆VTR/∆T”.

The value of the constant current limit current

”Ilim”.

The value of the off-hook current threshold

”ITH”.

The value of the ring trip rectified average

threshold current ”IRTH”.

The value of the required self generated nega-

tive battery ”VBATR” in ring mode (max value is

70V). This value can be obtained from the de-

sired ring peak level +5V.

The value of the maximum current peak sunk

from Vpos ”IPK”.

STLC3065

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