alc250-lf Realtek Semiconductor Corporation, alc250-lf Datasheet - Page 5

• Manufacturer Part Number: alc250-lf
• Description: Two-channel Ac?97 2.3 Audio Codec With Equalizer
• Manufacturer: Realtek Semiconductor Corporation

1. General Description
The ALC250 is a 20-bit DAC and 18-bit ADC full duplex AC'97 2.3 compatible stereo audio CODEC designed for PC multimedia
systems, including host/soft audio and AMR/CNR based designs. The ALC250 incorporates proprietary converter technology to
achieve a high SNR, greater than 100 dB, sensing logics for device reporting, and Universal Audio Jack® to enhance user
convenience. The ALC250 AC'97 CODEC supports multiple CODEC extensions with independent variable sampling rates and
built-in 3D effects. The ALC250 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 circuitry of the ALC250 CODEC operates from a +3.3V digital power and +5V analog power supply with EAPD (External
Amplifier Power Down) control for use in notebook and PC applications. The ALC250 integrates a 50mW/20Ω headset audio
amplifier into the CODEC, saving BOM costs. The ALC250 also supports the SPDIF out function, which complies with AC'97 2.3,
and offers easy connection of PCs to consumer electronic products, such as AC3 decoder/speaker and mini disk devices.
The ALC250 CODEC supports host/soft audio from Intel ICHx chipsets as well as audio controller based
VIA/SIS/ALI/AMD/nVIDIA/ ATI chipset. Bundled Windows series drivers (WinXP/ME/2000/98/NT), EAX/ Direct Sound 3D/
I3DL2/ A3D compatible sound effect utilities (supporting Karaoke, 26-kind of environment sound emulation, and 10 software
equalizer bands), HRTF 3D positional audio and Sensaura™ 3D (optional) provide an excellent entertainment package and game
experience for PC users. Integrated 14.318M 24.576MHz PLL generate required clock to eliminate the need for external crystal.
The ALC250 also builds-in seven bands of digital hardware equalizer and cascades one lowpass filter, five bandpass filters, and one
highpass filter. It optimizes frequency response on mobile PC speakers.
2. Features
Two-Channel AC’97 2.3 Audio Codec
Built- in 7 Bands of Digital Hardware Equalizer
Single chip with high S/N ratio (>100 dB)
Meets performance requirements for audio on
Meets Microsoft WHQL/WLP 2.0 audio
20-bit DAC and 18-bit ADC resolution
Compliant with AC’97 2.3 specifications
Support of S/PDIF out is fully compliant with
Three analog line-level stereo inputs with 5-bit
High quality differential CD input
Two analog line-level mono input: PCBEEP,
Supports double sampling rate (96KHz) of DVD
Two software selectable MIC inputs
+6/12/20/30dB boost preamplifier for MIC input
Stereo output with 6-bit volume control
Mono output with 5-bit volume control
Headphone output with 50mW/20Ω amplifier
3D Stereo Enhancement
for Optimizing Speaker Response
PC99/2001 systems
requirements
-LINE/HP-OUT, MIC-IN and LINE-IN sensing
-14.318MHz- 24.576MHz PLL saves crystal
-12.288MHz BITCLK input can be consumed
-Integrated PCBEEP generator to save buzzer
-Interrupt capability
-Page registers and Analog Plug&Play
AC’97 rev2.3 specifications
volume control: LINE_IN, CD, AUX
PHONE-IN
audio playback
1
Multiple CODEC extension capability
External Amplifier Power Down (EAPD)
Power management and enhanced power saving
Stereo MIC record for AEC/BF application
DC Voltage volume control
Auxiliary power to support Power Off CD
Adjustable VREFOUT control
EQ operation can be controlled by 2 pins of
2 Universal Audio Jack (UAJ)® for front panel
Support 32K/44.1K/48K/96KHz of S/PDIF output
Support 32K/44.1K/48KHz of S/PDIF input
Power support: Digital: 3.3V; Analog: 3.3V/5V
Standard 48-Pin LQFP Package
EAX™ 1.0&2.0 compatible
Direct Sound 3D™ compatible
A3D™ compatible
I3DL2 compatible
HRTF 3D Positional Audio
Sensaura™ 3D Enhancement (optional)
10 Bands of Software Equalizer
Voice Cancellation and Key Shifting in Kara
AVRack
Configuration Panel to improve Experience of
capability
features
serial bus
OK mode
User
®
Media Player
ALC250 DataSheet
Rev1.3