PEB3265 Infineon Technologies Corporation, PEB3265 Datasheet - Page 52

• Manufacturer Part Number: PEB3265
• Description: (PEB326x / PEB426x) Dual Channel Slicofi-2 / Slic Duslic
• Manufacturer: Infineon Technologies Corporation

Preliminary
3.5
With the 170 V technology used for the SLIC, a ringing voltage of up to 85 Vrms can be
generated on-chip without the need for an external ringing generator. The SLICOFI-2x
generates a sinusoidal ringing signal that causes less noise and cross-talk in
neighboring lines than a trapezoidal ringing signal. The ringing frequency is
programmable from 3 to 300 Hz.
SLIC-E/-E2, SLIC-S/-S2 and SLIC-P support different ringing methods (see
Chapter
3.5.1
A typical ringer load can be thought of as a resistor in series with a capacitor. Ringer
loads are usually described as a REN (Ringer Equivalence Number) value. REN is used
to describe the on-hook impedance of the terminal equipment, and is actually a
dimensionless ratio that reflects a certain load. REN definitions vary from country to
country. A commonly used REN is described in FCC part 68 that defines a single REN
as either 5 k , 7 k or 8 k of AC impedance at 20 Hz. The impedance of an n-multiple
REN is equivalent to parallel connection of n single RENs. In this manual, all references
to REN assume the 7 k
For example, a 1 REN and 5 REN load would be:
Figure 25
3.5.2
Once the subscriber has gone off-hook, the ringing signal must be removed within a
specified time, and power must start feeding to the subscriber's phone. There are two
ring trip methods:
DC Ring Trip Detection
Most applications with DuSLIC are using DC ring trip detection. By applying a DC offset
together with the ringing signal, a transversal DC loop current starts to flow when the
subscriber goes off-hook. This DC current is sensed by the SLIC and in this way used
as an off-hook criterion. The SLIC supplies this information to the SLICOFI-2x at the IT
pin. The SLICOFI-2x continuously integrates the sensed line current I
Data Sheet
3.5.3).
Ringing
Ringer Load
Ring Trip
6930
Typical Ringer Loads of 1 and 5 REN Used in US
1 REN
8 µF
model.
52
1386
Functional Description
5 REN
40 µF
TRANS
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2000-07-14
DuSLIC
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