Technical information

LCP22

6/10

Doc ID025775 Rev 3

For a line card with 50

Ω of series resistors which has to be qualified under GR-1089 1000 V

10/1000 µs surge, the present current through the LCP22 is equal to:

I surge = 1000 / (10 + 50) = 17 A

The LCP22 topology is particularly optimized for the new telecom applications such as fiber

in the loop, WLL systems, and decentralized central office, for example.

Figure 8. Protection of SLIC with positive and negative battery voltages

Figure 8 shows the classical protection topology for SLIC using both positive and negative

battery voltages. With such a topology the SLIC is protected against surge over +Vb and

lower than -Vbat. In this case, +Vb can be programmed up to +120 V while -Vbat can be

programmed down to -120 V.

Gn

Gp

GND

TIP

RING

-Vbat

+Vb

LCP22

220nF

SLIC

Rs (*)

Rs (*)

Line

Line card

TIP

RING

220nF

Rs (*) = PTC or Resistor fuse