Single-Chip Modem. 73K222AU Datasheet

73K222AU Modem. Datasheet pdf. Equivalent

Part 73K222AU
Description Single-Chip Modem
Feature ® TDK SEMICONDUCTOR CORP. DESCRIPTION The 73K222AU is a compact, high-performance modem which includ.
Manufacture TDK
Datasheet
Download 73K222AU Datasheet



73K222AU
®
TDK SEMICONDUCTOR CORP.
DESCRIPTION
The 73K222AU is a compact, high-performance
modem which includes a 8250A/16C450 compatible
UART with the 1200 bit/s modem function on a
single chip. Based on the 73K222L 5V low power
CMOS modem IC, the 73K222AU is the perfect
modem/UART component for integral modem
applications. It is ideal for applications such as
portable terminals and laptop computers. The
73K222AU is the first fully featured modem IC which
can function as an intelligent modem in integral
applications without requiring a separate dedicated
microcontroller. It provides for data communication
at 1200, 600, and 300 bit/s in a multi-mode manner
that allows operation compatible with both Bell
212A/103 and CCITT V.22/V.21 standards. The
digital interface section contains a high speed
version of the industry standard 8250A/16C450
UART, commonly used in personal computer
products. A unique feature of the 73K222AU is that
the UART section can be used without the modem
function, providing an additional asynchronous port
at no added cost. The 73K222AU is designed in
CMOS technology and operates from a single +5V
supply. Available packaging includes 40-pin DIP or
44-pin PLCC for surface mount applications.
73K222AU
Single-Chip Modem
Modem with UART
FEATURES
April 2000
Modem/UART combination optimized for
integral bus applications
Includes features of 73K222L single-chip modem
Fully compatible 16C450/8250 UART with
8250B or 8250A selectable interrupt emulation
High speed UART will interface directly with
high clock rate bus with no wait states
Single-port mode allows full modem and
UART control from CPU bus, with no
dedicated microprocessor required
Dual-port mode suits conventional designs
using local microprocessor for transparent
modem operation
Complete modem functions for 1200 bit/s (Bell
212A, V.22) and 0-300 bit/s (Bell 103, V.21)
Includes DTMF generator, carrier, call-
progress and precise answer-tone detectors
for intelligent dialing capability
On chip 2-wire/4-wire hybrid driver and off-
hook relay buffer
Speaker output with four-level software driven
volume control
Low power CMOS (40 mW) with power down
mode (15 mW)
Operates from single +5V supply
BLOCK DIAGRAM
TXD
XTL1 XTL2 CLK
UD0
UD1
UD2
UD3
UD4
UD5
UD6
UD7
UA0
UA1
UA2
1.8432 MHz
8250A / 16C450
UART
INTERNAL DATA
73K222AL
2W/4W
HYBRID
2
INT OUT1
RXD-INPUT
OH
RELAY
DRIVER
TXA1
TXA2
RXA
SPKR
( ) / MA0
( ) / MA1
(UA3) / MA2
DATA / ( )
/( )
/ (N/C)
( ) / DCLK
( )/
INTRPT ( ) PRST RESET RXD
VDD VREF GND ISET STNDLN



73K222AU
73K222AU
Single-Chip Modem
with UART
FUNCTIONAL DESCRIPTION
The 73K222AU integrates an industry standard
8250/16C450 UART function with the modem
capability provided by the 73K222L single chip
modem IC. The 73K222AU is designed specifically
for integral microprocessor bus intelligent modem
products. These designs typically require the
standard 8250 or higher speed 16450 UART to
perform parallel-to-serial and serial-to-parallel
conversion process necessary to interface a parallel
bus with the inherently serial modem function. The
73K222AU provides a highly integrated design
which can eliminate multiple components in any
integral bus modem application, and is ideal for
internal PC modem applications.
The 73K222AU includes two possible operating
modes. In the dual-port mode, the device is suitable
for conventional plug-in modem card designs which
use a separate local microprocessor for command
interpretation and control of the modem function. In
this mode, a dedicated microcontroller
communicates with the 73K222AU using a separate
serial command port. In the single-port mode the
main CPU can control both the UART and modem
function using the parallel data bus. This allows very
efficient modem design with no local microprocessor
required for dedicated applications such as laptop
PC’s or specialized terminals.
To make designs more space efficient, the
73K222AU includes the 2-wire to 4-wire hybrid
drivers, off-hook relay driver, and an audio monitor
output with software volume control for audible call
progress monitoring. As an added feature the UART
function can be used independent of the modem
function, providing an added asynchronous port in a
typical PC application with no additional circuitry
required.
UART FUNCTION (16C450)
The UART section of the 73K222AU is completely
compatible with the industry standard 16C450 and
the 8250 UART devices. The bus interface is
identical to the 16450, except that only a single
polarity for the control signals is supported. The
register contents and addresses are also the same
as the 16C450. To insure compatibility with all
existing releases of the 8250 UART design, external
circuitry normally used in PC applications to emulate
8250B or 8250A interrupt operation has been
included on the 73K222AU. A select line is then
provided to enable the desired interrupt operation.
The UART used in the 73K222AU can be used with
faster bus read and write cycles than a conventional
16C450 UART. This allows it to interface directly
with higher clock rate microprocessors with no need
for external circuitry to generate wait states.
The primary function of the UART is to perform
parallel-to-serial conversion on data received from
the CPU and serial-to-parallel conversion on data
received from the internal modem or an external
device. The UART can program the number of bits
per character, parity bit generation and checking,
and the number of stop bits. The UART also
provides break generation and detection, detection
of error conditions, and reporting of status at any
time. A prioritized maskable interrupt is also
provided.
The UART block has a programmable baud rate
generator which divides an internal 1.8432 MHz
clock to generate a clock at 16 x the data rate. The
data rate for the transmit and receive sections must
be the same. For DPSK modulation, the data rate
must be 1200 Hz or 600 Hz. For FSK modulation,
the data rate must be 300 Hz or less. The baud
generator can create a clock that supports digital
transfer at up to 115.2 kHz. The output of the baud
generator can be made available at the CLK pin
under program control.
MODEM FUNCTION (73K222AL)
The modem section of the 73K222AU provides all
necessary analog functions required to create a
single chip Bell 212A/103 and CCITT V.22/V.21
modem, controlled by the system CPU or a local
dedicated microprocessor. Asynchronous 1200 bit/s
DPSK (Bell 212A and V.22) and 300 baud FSK (Bell
103 and V.21) modes are supported.
The modem portion acts as a peripheral to the
microprocessor. In both modes of operation, control
information is stored in register memory at specific
address locations. In the single-port mode, the
modem section can be controlled through the
16C450 interface, with no external microcontroller
required. The primary analog blocks are the DPSK
modulator/demodulator, the FSK modulator/
demodulator, the high and low band filters, the AGC,
the special detect circuitry, and the DTMF tone
generator. The analog functions are performed with
switched capacitor technology.
2







@ 2014 :: Datasheetspdf.com :: Semiconductors datasheet search & download site (Privacy Policy & Contact)