MT8924 Datasheet, PDF (1/14 Pages) Mitel Networks Corporation – PCM Conference Circuit (PCC) Preliminary Information

MT8924
®
PCM Conference Circuit (PCC)
Preliminary Information
Features
• Supports up to 10 independent conferences for
up to 32 PCM Voice Channels
• ST-BUS compatible 2.048 Mb/s PCM Serial
Interface (also supports 1.536 Mb/s and 1.544
Mb/s data rates)
• Per channel digital gain control (0/-3/-6 dB)
• Parallel microprocessor port for device control
• Programmable noise suppression
• External Tone Input
• Pin selectable A/µ-Law format
• Low power CMOS technology
• Available in 24 Pin PDIP and SOIC packages
Applications
• Digital PBX / KTS
• Conference bridges
• Digital C.O. switches
ISSUE 1
Ordering Information
MT8924AE 24 Pin Plastic DIP
MT8924AS 24 Pin SOIC
0^°C to +70^°C
April 1994
Description
The MT8924 is designed to provide conference call
capability in digital switching systems. It allows up to
10 independent conferences to be set for up to 32
PCM voice channels.
A/µ-Law companded data from the PCM input port is
converted to linear format, processed by a dedicated
arithmetic unit, re-converted to companded format
and then sent to the PCM output port.The PCM
output signal contains all the information of each
channel connected in conference except its own.
Programmable attenuation and noise suppression
are provided for channels connected in conference
or transparent mode. Additionally, an input for an
external tone is featured that can be used as a signal
to indicate to connected parties that they are on a
conference call.
OS
Attenuation/Noise Suppression
µ/A-Law
to
Linear
Overflow
Channel RAM
and
Adder
Linear
to
µ/A-Law
DSTi
Serial-to-Parallel
Conversion
Parallel-to-Serial
Conversion
DSTo
PCM Mode
Control
Timebase
PCM Tone
Generator
Control
RESET A/µ
Cki F0i Cko
TF TD
RD WR D0-D7 CS C/D
Figure 1 - Functional Block Diagram
8-3