OCM-22.pdf 데이터시트 (총 4 페이지) - 파일 다운로드 OCM-22 데이타시트 다운로드

No Preview Available !

www.DataSheet4U.com
Product Brief Rev 1.0
April 2005
OCM-22
One-Chip Modem for Embedded Applications
Features
Controller and data pump in a single 48-pin TQFP
with two integrated peripheral interfaces:
— Partial ISA (8-bit parallel).
— RS232.
Data mode capabilities range:
— V.22bis: 2400 bits/s.
— V.22: 1200 bits/s.
— V.23: 1200/600 bits/s.
— V.21: 300 bits/s.
— Bell 212A: 1200 bits/s.
— Bell 103: 300 bits/s.
Serial DTE interface:
— Hardware and software flow control.
— Asynchronous data format: 19,200 bits/s, 8-bit
data, no parity, 1 stop bit.
Parallel DTE interface for connection to system I/O
or memory bus.
DAA support:
— CSP1035A silicon DAA.
— CSP1034C with transformer DAA.
Supports low-cost, call-progress speaker.
Support for country-specific settings
(homologation) under host control.
Supports extension phone detection for set-top
box applications when used with CSP1035A DAA.
Customized feature set using code downloads into
on-chip RAM.
Internal PLL to generate high-speed clocks from
external low-cost crystal.
Single 3.3 V supply.
Type 1 caller ID support (US, UK, France, Ger-
many, and Spain).
Introduction
OCM-22 is a low-cost modem solution for low-speed
embedded applications. OCM22 includes a simplified
AT command set and supports data rates from
300 bits/s (V.21) to 2400 bits/s (V.22bis) and only
requires a CSP1034 or CSP1035A to make a com-
plete modem.
OCM-22 provides a choice of two system interfaces,
a serial interface or an 8-bit parallel interface. The
serial interface can be used in systems that have an
available serial port. In other systems, the parallel
interface can be I/O or memory mapped onto typical
processor buses.
In typical applications, OCM-22 is paired with Agere's
CSP1035A silicon DAA to implement a low-cost
worldwide modem. OCM-22 can also be used with
Agere's CSP1034 line codec for traditional trans-
former-based DAA designs.
Applications
Set-top-box
Verification machines
Point of sale
Franking machines
Other low-speed data

No Preview Available !

Product Brief Rev 1.0
April 2005
OCM-22
One-Chip Modem for Embedded Applications
Functional Description
The Agere Systems OCM-22 chip set is a two-chip solution consisting of an Agere Systems OCM-22 and a
CSP1034C or CSP1035A. A block diagram of the OCM-22 chip sets are illustrated in Figure 1 and Figure 2.
AGERE SYSTEMS
OCM-22 CONTROLLERLESS MODEM CHIP
OCM-22
SYSTEM
MICRO-
PROCESSOR
PARALLEL/
SERIAL
48-PIN
TQFP
U-DAA
CSP1035A (LINE-POWERED)
LINE
CODEC
UNIVERSAL
DAA
48-PIN TQFP
REMAINING
COMPONENTS
FOR
U-DAA
TELEPHONE
LINE
Figure 1. OCM-22 + CSP1035A Universal DAA Chip Set Block Diagram
D5-9559 (F)a R.02
AGERE SYSTEMS
OCM-22 CONTROLLERLESS MODEM CHIP
OCM-22
SYSTEM
MICRO-
PROCESSOR SERIAL/
PARALLEL
48-PIN
TQFP
CSP1034C LINE
CODEC
48-PIN TQFP
STANDARD
DAA CIRCUIT
TELEPHONE
LINE
Figure 2. OCM-22 + CSP1034C Chip Set Block Diagram
5-9560 (F)a R.02
DIA Port
OCM-22 provides a system interface for use in embedded applications that requires only two address lines, a read/
write strobe, and a single chip select. The interface feeds directly into the DIAs four registers.
The following diagram shows how the host system and the OCM-22 interface. In this configuration, external logic
decodes the address that selects the DIA port, and the embedded application accesses the four control registers
associated with the DIA port to communicate with OCM-22. This configuration also allows a clean interface to
external plug-and-play and PCMCIA interface devices.
Agere Systems Inc.
2

No Preview Available !

Product Brief Rev 1.0
April 2005
Functional Description (continued)
OCM-22
One-Chip Modem for Embedded Applications
OCM-22 DEVICE
DATA[7:0]
ADDR[1:0]
READN
WRITEN
INTRPT
ADDRESS
DECODE
HD[7:0]
HA[1:0]
HRDN
HWRN
HINTR
HCSN
Figure 3. Parallel Interface to DIA Port
5-8104 (F) a
Internal PLL for Low-Speed Crystal Support
OCM-22 supports low-speed, external crystals by
incorporating a PLL to support lower-cost crystals and
to ease the effort of minimizing EMI. If future code
needs higher clock rates, an internal multiplier can pro-
vide this without recertification or redesign of the exter-
nal hardware. OCM-22 requires an external 29.4912
MHz crystal or oscillator.
PWM Speaker Interface
The speaker driver employs a pulse-width modulated
algorithm, where 8-bit two's complement data is modu-
lated by a triangle wave. The following diagram shows
the recommended speaker configuration. This inex-
pensive configuration drives a low-impedance speaker
while obtaining a suitable volume. The SPKR signal is
fed to a transistor through a low-pass filter to remove
the carrier signal (cut-off frequency = 4 kHz).
Power Requirements
Both the OCM-22 device and the CSP1034C are
manufactured in low-power CMOS technology and are
designed to operate using only a single 3.3 V supply.
During operation, OCM-22's on-chip PLL can be set to
provide only the minimum internal clock rate required.
The CSP1035A is also manufactured in low-power
CMOS technology. However, the CSP1035A is fully
line powered. A shunt regulator maintains a monitored
2.7 V supply, during off-hook conditions. If the voltage
falls below 2.2 V, the chip saves its registers and goes
into reset. This allows the CSP1035A to retain the reg-
ister settings during a call bridge where the tip/ring volt-
age can collapse to 0 V for up to 400 ms and start up
again at the completion of the call break.
+3.3 V
AT-08
SPKR
3.3 k
10 k6800 pF
FDV301N
Agere Systems Inc.
Figure 4. Lower-Impedance Speaker Configuration
5-8105 (F)
3