73M2921
Advanced Single
Chip Modem
Advanced Information
February 1999
DESCRIPTION
FEATURES
The 73M2921 is a CMOS integrated circuit which
provides all the modem “Data Pump” functions
required to implement a V.22bis data modem. It
consists of a DSP (Digital Signal Processor) core
with RAM and ROM data memory, ROM instruction
memory, and register mapped input/output functions
including timers, interrupts, Σ∆ ADC and DAC ports
and Serial Data I/O.
•
•
Automatic handshaking for all data modes
Data Speeds:
V.22bis - 2400 b/s
V.22, Bell 212 - 1200 b/s
V.21, Bell 103 - 300 b/s
V.23 1200 b/s - 75 b/s
Bell 202 1200 b/s
Once the 73M2921 has been initialized, all call
progress and modem handshaking is automatic.
The default conditions may be changed as required
for country specific or custom applications.
•
Facsimile Speeds:
V.29 - 9600, 7200 b/s
V.27ter - 4800, 2400 b/s
V.21 ch 2 - 300 b/s
The 73M2921 provides DTMF tone generation and
detection, precise call progress detect and ADSI
functions such as CAS tone detection.
•
•
•
•
•
V.8bis applications
Designed for 3.3 and 5-Volt systems.
Low operating power.
Other features include a parallel interface control
port between the host processor and the 73M2921.
A
synchronous serial data channel provides
Speaker monitor output
synchronizing clocks RXCLK and TXCLK from the
modem pump to the controller.
Provides 2 tone generators for single tone or
DTMF generation
The 73M2921 contains an oscillator and power
control features.
•
•
Provides DTMF tone detection
Provides 4 precise and 1 imprecise call
progress filters and corresponding detect
The host controller function can be implemented with
a 73M2910 communications micro controller or
another commercial microcontroller (such as the
68302). The 73M2921 has been optimized to work
with the 73M2910 synchronous serial port.
bits with programmable
frequencies
thresholds and
•
•
•
•
Provides CAS tone detection for ADSI and
CLASS feature support
Supports parallel (8 bit) control, and
synchronous serial data I/O
73M2921 provides a microcontroller inter-
rupt
Packaging: The 73M2921 is available in a
QFP production package. A PGA package is
available for prototyping
Rev M