ISL5586 Datasheet, PDF (16/20 Pages) Intersil Corporation – Low Power Ringing SLIC for Home Gateways

ISL5586
Equations 48 and 60 can be combined to re-write the 4-wire
to 4-wire gain equation.
V^-V----_RT^{----XX----44---WW---}
=
–2.8



Z^----_O^-------+^------2^-Z--R^--L---_P^------+^-----Z^----_L^-_{}
× _Z-^Z----^0L-
(EQ. 61)
Simplifying the above yields the 4-wire to 4-wire gain.
-^V----^T----^X----⁴---^W---
V_RX4W
=

– 2.8 

Z^----_O^-------+^------2^-Z--R^--0---_P^------+^-----Z^----_L^-_{}
(EQ. 62)
I_L
R_P1
20
V_IN
+_-
Z_L
V
TR
TIP
RING
20
R_P2
200K
-
+
+_-
200K _4R
4R
4R
4R
1.4R
R
200K
-
V_RXP
V_RX ⁺
V_RXM
200K
1.4R
R
1:1
V_ZO
T_A
R_S
3R
-
8K
+
V_SA
3R
-IN
C_FB
V_FB
R
R
-
+
V_TXP
+
V_TX4W
-
V_TXM
FIGURE 13. SCHEMATIC FOR 2-WIRE TO 4-WIRE GAIN DERIVATION
R_P1
+
T
V_{2W ZL IL}
-
R
R_P2
200K
20
-
+
20
+_-
200K _4R
4R
4R
4R
1.4R
200K
-
V_RX ⁺
200K
1.4R
1:1
V_ZO
T_A
R_S
3R
-IN
-
8K
+
V_SA
3R
C_FB
R
V_FB
R ^VRXP
R ^VRXM
R
-
+
+_- V_RX4W
V_TXP
-
V_TX4W
+
V_TXM
FIGURE 14. SCHEMATIC FOR 4-WIRE TO 4-WIRE GAIN DERIVATION
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