PEB2445NV1.2 Lantiq, PEB2445NV1.2 Datasheet - Page 26

• Manufacturer Part Number: PEB2445NV1.2
• Manufacturer: Lantiq

Specifications of PEB2445NV1.2

• Lead Free Status / Rohs Status: Supplier Unconfirmed

• The bits of a time-slot are numbered 0 through 7. Bit 0 (MSB) of a time-slot is the first
Preparation of the Input Data (Input Buffer)
The PEB 2445 works in 2048-, 4096- or 8192-kbit/s PCM systems. The frame frequency
is 8000 Hz in all 3 types of systems. Therefore a frame consists of 32-, 64- or
128 time-slots of 1 byte each, respectively. In order to fill the speech memory, which has
a fixed capacity of 512 channels, either 16-, 8- or 4 input lines are necessary,
respectively. Thus, in 4- and 8-MHz systems only some of the 16 input lines can be used.
Moreover, the PEB 2445 can also work with two different input data rates
simultaneously. In this case some of the PCM-input lines operate at one data rate, while
others operate at another. Table 2 states how many input lines are operating at the
different data rates for all possible input data rate combinations. In the following they will
be referred to as input modes.
The input mode the PEB 2445 is actually working in has to be programmed into the mode
register, bits Ml1, Ml0, MO1, MO0. In chapter 4.1 you will find a complete description
which input line is connected to which system, for each of the input modes.
Table 2
Possible Input Modes
Input Modes
16
8
4
2
The PEB 2445 runs with either a 4096- or a 8192-kHz device clock as selected with
CFR:CPS. Data rates and clock frequencies may be combined freely. However,
processing 8192-kbit/s data, an 8192-kHz clock must be supplied.
The preparation of the input data according to the selected input mode is made in the
input buffer. It converts the serial data of a time-slot to parallel form.
In standard configuration time-slot 0 begins with the rising edge of the SP pulse as
shown in upper half of figure 12 denoted CSR:(0000XXXX).
Definitions
• The PEB 2445 works with either an 8192-kHz clock or a 4096-kHz clock. Henceforth,
4
Semiconductor Group
the respective clock periods are referred to as
bit to be received or transmitted by the MUSAC-A, bit 7 (LSB) the last.
8192
4096
+
+
2048
4096
8192
8
8
2048
2048
kbit/s
kbit/s
kbit/s
kbit/s
kbit/s
26
t
CP8
and
t
CP4
.
Functional Description
Type
Single mode
Single mode
Single mode
Mixed mode
Mixed mode
PEB 2445
02.96