PRODUCT OVERVIEW

The AD1803/AD1804 chipset allows the implementation of a low-cost full Modem DAA Line Interface and codec with minimal external components. The AD1803 can also be used as a stand-alone codec for voice/handset/telephony applications, or as a cellular telephone interface.
The AD1803 is an Intel AC’97 Rev 2.1-compliant modem codec (refer to Intel’s AC’97 specifications at www.intel.com ) with selectable AC’97 or a DSP-style serial interface.
The AD1803 codec uses high-performance sigma-delta ADC and DACs with programmable gain/attenuation. It has a digital monitor output with selectable mix from ADC and DAC channels for call progress monitoring. The AD1803 supports ring validation and wake-up interrupt output signalling. The AD1803 has programmable filters dedicated to impedance synthesis and when used with the AD1804, it provides a complete digital line termination impedance synthesis control loop.
The AD1804 is a solid-state line-side analog phone interface device that replaces a conventional discrete DAA. The AD1804 eliminates the need for transformer, relays, opto-isolators and a 2-to-4-wire hybrid. The AD1804 uses high-performance sigma-delta ADC and DACs with programmable gain/attenuation. It has digitally selectable line termination impedances.

FEATURES

Low Power Modem Codec AD1803 and Silicon DAA AD1804
AD1803 Can Be Used as a Stand-Alone Modem/Voice/Telephony Codec Independent of the AD1804
Intel AC’97 Rev 2.1-Compliant Modem CodecImplementation
AC’97 or DSP Style Serial Interface
Supports all Modem/Fax Standards Including V.90
Software Programmable DAA and Compliant with U.S. and International PTT Standards
FCC and CTR21 Approved
Capacitively Coupled Clock and Data Interface Across Isolation Barrier
Multiple Crystal/Clock Rates Supported
Programmable Gain, Attenuation and Mute
On-Chip Signal Filters
Digital Interpolation and Decimation Filters
Analog Output Low Pass
Programmable Sample Rates
From 6.4 kHz to 16 kHz
With 1 Hz, 8/7 Hz and 10/7 Hz Resolution
Digital Monitor Speaker Output
Integrated Ring Detector and Support for Soft Caller-ID Decode
24-Lead TSSOP Package
0.6 mm CMOS Technology
Operation from 3.3 V or 5 V Supply
Advanced Power Management
Supports Wake-Up on Ring from D3-Cold System State

APPLICATIONS
Modems (PC and Embedded)
Voice and Telephony
Fax Machines, Answering Machines, Speakerphones
PBX Systems
Smart Appliances