1. General Description
The ALC221 is a High Definition Audio Codec that integrates 4-channel DAC, 4-channel ADC, and a
mono and filter-less Class-D Speaker Amplifier with 2 Watt (rms) output power.
The 4-channel DAC and 4-channel ADC support two independent stereo sound outputs and two
independent stereo inputs simultaneously, supporting multiple streaming playback and output for
multimedia applications and voice communication. The codec has high performance and characteristics
meets WLP (Windows Logo Program) audio requirements for Windows XP, Windows Vista and
Windows 7 systems.
The ALC221 supports stereo digital microphone input with boost gain and digital volume control. With
Realtek second generation of software Acoustic Echo Cancellation (AEC), Beam Forming (BF), and
Noise Suppression (NS) technology, significantly improving voice input quality for VoIP application on
PCs.
ALC221 has headphone amplifier can drive 32Ω headphone load without external DC blocking
capacitors, eliminating pop noise caused by these capacitors. Addition to the cap-free headphone output
port (HP-OUT), port LINE-OUT is also designed as a line level output without the need for DC blocking
capacitors, that can keep away from pop noise whiling line level output connected to external power
speaker.
The integrated mono Class-D amplifier is a filter-free design to directly drive mini speaker with as low as
4Ω impedance. Its maximum output power exceeds 2 Watt at 5V power supply. The inside high pass
filter with selectable cut off frequency can prevent speaker burn up by low frequency sound. The class D
amplifier output power also could be limited to avoiding damage mini speaker. ALC221 has over current
and short circuit detection to protect integrated Class D amplifier and power system. Class D amplifier
output will be shut down when connected speaker is broken with short and over-heating. More than
protection functions, ALC221 has spread spectrum and slew rate control for Class D carrier frequency
can reduce EMI radiation when Class D amplifier is in active.
Support for 16/20/24-bit S/PDIF output with up to 192kHz sample rate offers easy connection of PCs to
consumer electronic products or transporting digital audio output to a High Definition Media Interface
(HDMI) transmitter.
The ALC221 supports host audio from the Intel chipsets, and also from any other HDA compatible audio
controller. With various software utilities like environment sound emulation, multiple-band and
independent software equalizer, dynamic range compressor and expander, optional DTS® CONNECT™
and Surround Sensation UltraPC™, SRS® TruSurround HD, SRS® Premium SoundTM and Dolby® Digital
Live, Dolby® PCEE program and 3rd party voice processing (Noise Suppression/Acoustic Echo
Cancellation/Beam Forming) technology, the ALC221 provides an excellent package for PC users
2. Features
2.1. Hardware Features
„ Meets WLP (Windows Logo Program) requirements for Windows XP, Vista and Windows 7
„ Analog DAC output with 97dB Signal-to-Noise Ratio (A-weighting)
„ Analog ADC input with over 90dB Signal-to-Noise Ratio (A-weighting)
„ 4-channel DAC supports 16/20/24-bit PCM format for independent two stereo channel playback
„ 4-channel ADC supports 16/20/24-bit PCM format for independent two stereo channel recording
„ All DACs supports 44.1k/48k/96k/192kHz sample rate
„ All ADCs support 44.1k/48k/96k/192kHz sample rate
„ S/PDIF-OUT support 16/20/24-bit format and 44.1/48/88.2/96/192kHz sample rate
„ Six stereo analog IO ports: LINE-OUT (output), MIC1 (input and output), MIC2 (input), LINE1
(input and output), LINE2 (input and output) and HP-OUT (output)
„ One mono port with Class D Amplifier to driver mini speaker: MONO-OUT
„ One stereo digital microphone input
„ Supports external PCBEEP input and built-in digital BEEP generator
„ PCBEEP pass through to port MONO-OUT (Class D amplifier), LINE-OUT-OUT an HP-OUT
„ Built in headphone amplifiers at port LINE1 and HP-OUT
„ Headphone amplifier at port HP-OUT does not require DC blocking capacitors
„ Port LINE-OUT is stereo output without DC blocking capacitors
„ Software selectable 2.3V/3.0V/4.0V VREFOUT as bias voltage for analog microphone input
„ Programmable +12/+24/+36dB boost gain for analog microphone input
„ Programmable boost gain and volume control for digital microphone input
„ Two jack detection pins each can detect up to 4 jacks
„ Supports 4-conductor type headset combo jack (stereo headphone output and mono microphone
input on a single jack)
Enhanced power management features for normal operation and standby mode
„ Mono Bridge-Tied Load Class-D amplifier at port-H (MONO-OUT) has 2Watt (rms) power for 4Ω
load speaker
„ Short circuit and over current protections for Class-D amplifier
„ Class D amplifier has high pass filter with selectable Cut-Off frequency to prevent low frequency
signal damaging speaker
„ Class D amplifier output with slew rate and spread spectrum control to reduce EMI radiation
„ Intel low power ECR HDA015-B compliant: supports power status control, jack detection, and
wake-up event in D3 mode
„ 2 GPIOs (General Purpose Input and Output) pins for customized applications
„ EAPD (External Amplifier Power Down) is supported
„ Supports Anti-pop mode when analog power AVDD is on and digital power is off
„ Built in a 5V-to-4.5V LDO to power analog circuitry
„ Power support: 3.3V digital core power; 1.5V~3.3V digital IO power for HDA link; 4.5V~5.5V
analog power; 4.5V~5.5V power stage voltage
„ 48-pin QFN ‘Green’ package
2.2. Software Features
„ Meet Windows Logo Program audio requirements for Windows Vista and Windows 7
„ Support Linux driver based on kernel 2.6.0 and later version
„ EAX™ 1.0 & 2.0 compatible
„ Direct Sound 3D™ compatible
„ I3DL2 compatible
„ HRTF 3D Positional Audio (Windows XP only)
„ Multi-band software equalizer and dynamic range control (expander, compressor, and limiter) with
adjustable parameters
„ Intuitive Configuration Panel (Realtek Audio Manager) to enhance user experience
„ Enhanced Microphone Acoustic Echo Cancellation (AEC), Noise Suppression (NS), and Beam
Forming (BF) technology for voice application
„ HDMI audio driver for Intel and AMD chipsets
„ Dolby® PCEE program™ (optional software feature)
„ DTS® CONNECT™, DTS® Surround Sensation UltraPC™ (optional software feature)
„ SRS® TruSurround HD, SRS® Premium SoundTM (optional software feature)
„ Fortemedia® SAM™ technology for voice processing (Beam Forming and Acoustic Echo
Cancellation) (optional software feature)
„ Creative® Host Audio program (optional software feature)
3. System Applications
„ Commercial desktop and laptop PCs
„ Net-book and MID (Mobile Internet Device) with High Definition Audio Controller