AC 97 Audio Codec

The ALC650 is an 18-bit, full duplex AC'97 2.2 compatible stereo audio CODEC designed for PC multimedia systems, including host/soft audio and AMR/CNR based designs. The ALC650 incorporates proprietary converter technology to achieve a high SNR, greater than 90 dB. The ALC650 AC'97 CODEC supports multiple CODEC extensions with independent variable sampling rates and built-in 3D effects.

The ALC650 CODEC provides two pairs of stereo outputs with independent volume controls, a mono output, and multiple stereo and mono inputs, along with flexible mixing, gain and mute functions to provide a complete integrated audio solution for PCs. The digital interface circuitry of the ALC650 CODEC operates from a 5V/3.3V power supply with EAPD (External Amplifier Power Down) control for use in notebook and PC applications.

The ALC650 integrates a 50mW/20ohm headset audio amplifier into the CODEC, which can save BOM costs. The ALC650 also supports an AC'97 2.2 compliant SPDIF out function which allows easy connection from the PC to consumer electronic products, such as AC3 decoder/speaker and mini disk.

The ALC650 CODEC supports host/soft audio from Intel 810/815/820/845 chipsets as well as audio controller based VIA/SIS/ALI chipsets. Bundled Windows series drivers (Win95/98/ME/2000/XP/NT) and sound effect utilities (supporting Karaoke, emulation of 26 sound environments, and 5-band equalizer) provide a more comprehensive entertainment package for PC users. Finally, internal PLL circuits generate required timing signals, eliminating the need for external clocking devices.

Features:

High-performance CODEC with high S/N ratio (>90 dB)

18-bit ADC and 20-bit DAC resolution

Compliant with AC'97 2.2 specifications

18-bit stereo full-duplex CODEC with independent and variable sampling rate

4 analog line-level stereo inputs with 5-bit volume control: LINE_IN, CD, VIDEO, AUX

2 analog line-level mono inputs: PC_BEEP, PHONE_IN

Mono output with 5-bit volume control

Stereo output with 5-bit volume control

6 channel slot selectable DAC output for multi-channel applications

2 MIC inputs, which are software selectable

Power management capabilities

3D Stereo enhancement

Embedded 50mW/20ohm OP at front LINE output

External amplifier power down capability

Digital S/PDIF output

Digital S/PDIF input (ALC650 Rev. E or later)

No external crystal/clock required

Supports 1 general purpose I/O pin

Power supply: digital: 3.3V; analog: 5V/3.3V

Standard 48-pin LQFP package