MT8880C Datasheet, PDF (1/18 Pages) Mitel Networks Corporation – ISO2-CMOS Integrated DTMFTransceiver

ISO²-CMOS MT8880C/MT8880C-1
®
Integrated DTMF Transceiver
Features
• Complete DTMF transmitter/receiver
• Central office quality
• Low power consumption
• Microprocessor port
• Adjustable guard time
• Automatic tone burst mode
• Call progress mode
Applications
• Credit card systems
• Paging systems
• Repeater systems/mobile radio
• Interconnect dialers
• Personal computers
Description
The MT8880C/C-1 is a monolithic DTMF transceiver
with call progress filter. It is fabricated in Mitel’s
ISO²-CMOS technology, which provides low power
dissipation and high reliability. The DTMF receiver is
ISSUE 2
May 1995
Ordering Information
MT8880CE/CE-1 20 Pin Plastic DIP
MT8880CC/CC-1
MT8880CS/CS-1
MT8880CN/CN-1
20 Pin Ceramic DIP
20 Pin SOIC
24 Pin SSOP
MT8880CP/CP-1 28 Pin Plastic LCC
-40°C to +85°C
based upon the industry standard MT8870
monolithic DTMF receiver; the transmitter utilizes a
switched capacitor D/A converter for low distortion,
high accuracy DTMF signalling. Internal counters
provide a burst mode such that tone bursts can be
transmitted with precise timing. A call progress filter
can be selected allowing a microprocessor to
analyze call progress tones. A standard
microprocessor bus is provided and is directly
compatible with 6800 series microprocessors. The
MT8880C-1 is functionally identical to the MT8880C
except for the performance of the receiver section,
which is enhanced to accept and reject lower signal
levels.
TONE
∑
D/A
Converters
IN+
IN-
GS
OSC1
OSC2
Tone Burst
Gating Cct.
+
Dial
-
Tone
Filter
Oscillator
Circuit
Bias
Circuit
Control
Logic
High Group
Filter
Low Group
Filter
Control
Logic
Row and
Column
Counters
Digital
Algorithm
and Code
Converter
Steering
Logic
Transmit Data
Register
Status
Register
Control
Register
A
Control
Register
B
Receive Data
Register
V_DD V_Ref V_SS
ESt
St/GT
Figure 1 - Functional Block Diagram
Data
Bus
Buffer
Interrupt
Logic
I/O
Control
D0
D1
D2
D3
IRQ/CP
Φ2
CS
R/W
RS0
4-33