1.4
1.4.1
102228A
CX06833-3x/4x SMXXD Modem Data Sheet
• Full-duplex speakerphone (FDSP) mode using optional CX20442 Voice Codec
(S models)
− Microphone and speaker interface
− Telephone handset or headset interface
− Acoustic and line echo cancellation
− Microphone gain and muting
− Speaker volume control and muting
• Built-in host/DTE interface
− Parallel 16550A UART-compatible interface up to 230.4 kbps
− Serial ITU-T V.24 (EIA/TIA-232-E) logical interface up to 115.2 kbps
• Downloadable architecture
• Direct mode (serial DTE interface)
• Flow control and speed buffering
• Automatic format/speed sensing
• Serial async/sync data; parallel async data
• Thin packages support low profile designs (1.6 mm max. height)
− CX06833 Modem device in 144-pin TQFP
− CX20442 VC in 32-pin TQFP
• +3.3V operation with +5V tolerant digital inputs
• Typical power use
− CX06833: 191 mW (Normal Mode); 53 mW (Sleep Mode)
− CX20442: 5 mW (Normal Mode)
Technical Overview
General Description
Modem operation, including dialing, call progress, telephone line interface, telephone
handset interface, optional voice/speakerphone interface, and host interface functions are
supported and controlled through the V.250, V.251, and V.253-compatible command set.
The modem hardware connects to the host via a parallel or serial interface as selected by
the PARIF input. The OEM adds a crystal circuit, telephone line interface, telephone
handset/telephony extension interface, voice/speakerphone interface, optional external
serial EEPROM, optional external ROM/flash ROM, optional external RAM, and other
supporting discrete components as supported by the modem model (Table 1-1) and
required by the application to complete the system.
Customized modem firmware can be supported by the use of external memory in various
combinations, e.g., either external ROM/flash ROM (up to 256 KB), or external serial
EEPROM (256 to 32 KB) and external RAM (up to 128 KB). To support country profile
addition or modification, external serial EEPROM (256 to 32 KB) can be installed.
Customized code can include OEM-defined commands, i.e., identification codes (I3),
identifier string (I4), manufacturer identification (+GMI), model identification (+GMM),
and revision identification (+GMR), as well as code modification.
Parallel interface operation is selected by PARIF input high.
Serial interface operation is selected by PARIF input low.
Conexant
1-5