L3000S Datasheet, PDF (23/29 Pages) STMicroelectronics – SUBSCRIBER LINE INTERFACE KIT

L3000S - L3030
A PP ENDI X
SLIC TEST CIRCUITS
Referring to the test circuit reported at the end of each SLIC data sheet here below you can find the proper
configuration for each measurement.
In particular : A-B : Line terminals
C : TX sending output on 4W side
D : RX receiving input on 4W side
E : TTX teletaxe signal input
RGIN : low level ringing signal input.
TEST CIRCUITS
Figure 1 : Symmetry to Ground.
Figure 2 : 2W Return Loss.
Figure 3 : Trans-hybrid Loss.
R_L
=
20
log
|ZL
|Z_L
−
+
Z|
Z|
=
20
log^{|2 VS|}
|E|
1
WC
<<
Z
Figure 4 : SendingGain.
T HL
=
20
log10
|V_S|
|V_R|
GS
=
20
l og10
|VR|
|VSO|
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