English
Language : 

MC33218A Datasheet, PDF (1/28 Pages) Motorola, Inc – Voice Switched Speakerphone with Microprocessor Interface
Freescale Semiconductor, IncO.rder this document by MC33218A/D
Advance Information
Voice Switched Speakerphone
with Microprocessor Interface
The Motorola MC33218A Voice Switched Speakerphone Circuit
incorporates the necessary amplifiers, attenuators, level detectors, and
control algorithm to form the heart of a high quality hands–free
speakerphone system. Included are a microphone amplifier with mute,
transmit and receive attenuators, a background monitoring system for both
the transmit and receive paths, and level detectors for each path. An AGC
system reduces the receive gain on long lines where loop current and power
are in short supply. A dial tone detector prevents fading of dial tone. A Chip
Disable pin permits conserving power when the circuit is not in use.
Additionally, the MC33218A has a serial data port which permits
microprocessor control of the receive volume level, microphone mute,
attenuator range, and selection of transmit, receive, idle or normal modes.
The data port can be operated at up to 1.0 MHz.
The MC33218A can be operated from a power supply, or from the
telephone line, requiring typically 4.6 mA. It can be used in conjunction with a
variety of speech networks. Applications include not only speakerphones,
but intercoms and other voice switched devices.
• Supply Voltage Range: 2.7 to 6.5 V
• Attenuator Range: 53 or 27 dB (Selectable)
• 2 Point Sensing with Background Noise Monitor in Each Path
• Microprocessor Port for Control of:
Volume Control (40 dB Range over 16 Levels)
Mute Microphone Amplifier
Force to Receive, Transmit, or Idle Modes
Attenuator Range Selection (27 or 53 dB)
• Chip Disable Pin Powers Down the Entire IC
• 24 Pin Narrow Body (300 mil) DIP and 24 Pin SOIC
Simplified Block Diagram
Microphone
VB
Tx Attenuator
Transmit
Out
Receive
VB
In
BNM Attenuator Control
VB
CLK
DATA
POR
DR
CD
VCC
VB
Serial
Port
Reg.
DTD
Rx Attenuator
MC33218A
BNM
VB
Speaker
Speaker Amplifier
This device contains 610 active transistors.
MC33218A
VOICE SWITCHED
SPEAKERPHONE WITH
µPROCESSOR INTERFACE
SEMICONDUCTOR
TECHNICAL DATA
24
1
P SUFFIX
PLASTIC PACKAGE
CASE 724
24
1
DW SUFFIX
PLASTIC PACKAGE
CASE 751E
PIN CONNECTIONS
CP2 1
XDI 2
CPT 3
TLI 4
TLO 5
VB 6
CT 7
CD 8
NC 9
CPR 10
RLI 11
RLO 12
24 VCC
23 TAO
22 MCO
21 MCI
20 POR
19 DR
18 DATA
17 CLK
16 RXI
15 RXO
14 RAO
13 GND
(Top View)
ORDERING INFORMATION
Device
Operating
Temperature Range Package
MC33218ADW
SO–24L
MC33218AP TA = – 40° to +85°C Plastic DIP
This document contains information on a new product. Specifications and information herein are © Motorola, Inc. 1995
subject to change without notice.
MOTOROLA ANALOG IC DEVICEFDoArTMA orGeoIntfoo:rwmwatwio.fnreOenscTahlies.cPoromduct,
1