PEF20550HV21XT Lantiq, PEF20550HV21XT Datasheet - Page 343

• Manufacturer Part Number: PEF20550HV21XT
• Manufacturer: Lantiq

Specifications of PEF20550HV21XT

• Lead Free Status / Rohs Status: Supplier Unconfirmed

Trunk lines connect the PBX to the central office (CO) network. Figure 117 gives an
or SICOFI-4 codec/filter devices, which allow the connection of two or four analog lines
per chip.
If an access to the ISDN world is desired, two options are possible:
For small PBXs, with only few external lines, one or several Basic Rate ISDN (BRI)
connections are best suited. Each BRI connection provides a capacity of two B channels
of 64 kBit/s and one D channel of 16 kBit/s. The BRI connection is usually performed via
the T interface to the Network Terminator 1 (NT1). The T interface is physically identical
to the S interface, all Siemens S
be used for that purpose. A PBX can also be connected directly via the U
the CO. In this case an IEC-Q device (2B1Q encoding) or an IEC-T (4B3T encoding) can
be used as layer-1 device.
Figure 117
Overview of Trunk Line Applications
5.9.2
overview of the different access possibilities to the central office.
One possibility is to use analog a/b lines. This is the most uncomplicated way since no
clock recovery from the CO is required, i.e. the PBX operates with a free running crystal
oscillator. The t/r access to the CO can easily be realized with one or several SICOFI
Semiconductor Group
PCM/Signaling
Backplane
IOM
PCM
®
-2 Trunk Line Applications
ELIC
HDLC
R
PBX Trunk Line Card
0
IDEC
IOM -2
interface devices (QUAT-S, SBCX, ISAC-S, SBC) can
µP
R
R
343
SICOFI -2
SICOFI -4
SBCX
QUAT-S
FALC54
IECQ
R
R
S
T
2m
NT1
NT1
U
t/r
t/r
k
Application Hints
U
U
U
k
k2
g2
k
Analog
Line
Analog
Line
Basic Rate
ISDN
Basic Rate
ISDN
Primary Rate
(CEPT, T1)
PEB 20550
Central Office
- interface to
PEF 20550
ITS08097
01.96
-
2