AS3521B Datasheet, PDF (1/3 Pages) ams AG – Advanced Audio Decoder

Product Brief AS3521B
Advanced Audio Decoder
AS3521B
PRODUCT BRIEF
1.
General Description
The chip is a fully integrated and highly flexible digital audio
decoder for the austriamicrosystems mobile music platform.
Main purpose of this platform is the integration of digital
audio decoder (MP3, AAC and other formats as future
option), micro controller unit, data interfaces and the analog
audio channels for reproduction of digital audio.
This codec-chip contains a high performance 18 bit digital
to analog converter. The dynamic range exceeds 95dB for
best audio quality, for multi media applications (audio
playback) within battery or line operated equipment.
An additional audio power amplifier can directly drive
external headphones or small 4Ω speakers with a power of
up to half a watt. The power-up is click- and pop-less due to
a smooth start-up circuitry. The overall distortion level is
always below 0.02%.
The microphone input amplifier contains an automatic gain
control (AGC) with a dynamic range of 40dB to generate an
amplified and compressed signal for the ADC, which
provides 14 Bit resolution at 8kHz sampling-rate.
Furthermore all necessary power management is included
such as bandgap reference and three voltage regulators.
The two 2.9V regulators are used internally (analog and
digital supply), but can also be used for external purposes
as well. The third output is designed to supply the digital
core, and is programmable to either 2.25V or 2.5V. The
performance of the regulators is excellent (noise, line- and
load-regulation) and allows the direct supply of sensitive
analog circuits.
Because of the internal supply and signal filtering only few
small external capacitors are required for de-coupling and
stabilising and lead to very low output noise.
The current consumption is very low and makes the chip
ideally for battery powered devices.
2. Key Features
Embedded 32-Bit RISC Controller
• MCU and DSP functionality
• Scaleable architecture
• User accessible controller/DSP/memory resources
• Boot ROM
• Clock speed: 16 - 65 MHz
Hardware Interfaces
• USB Interface version 1.1 (support of MSC)
• MultiMediaCard / Secure Digital Card Interface
(support of MMC mode)
• Smart Media Card Interface
• NAND Flash Interface
• I²C Slave Interface (for access to control registers)
• SPI (master or slave)
• General Purpose I/O Lines (40)
On chip DCDC Converter
• 1.0 to 5.5V input voltage range
4 On-chip high performance voltage regulators
• Digital Supply, 2.9V
• Analog Supply, 2,9V
• Core Supply, 2.25V
• USB Transceiver Supply, 3.2V
18 Bit stereo DAC
• Dynamic range typ. 93 dB
• THD typ. -85dB
• De-emphasis for 32 kHz, 44.1 kHz and 48 kHz
Stereo power audio amplifier
• Max. 2x 0.5W @ 4Ω
• Analog volume control –39dB to +3dB, 3dB steps
including mute)
• Click- and pop-less startup and power down
• Auxiliary inputs for additional audio sources
Microphone input
• 14 Bit Σ∆−ADC mono
• 24kHz FM-quality recording
• Automatic gain control (AGC)
• Audio Formats: general platform for popular digital
audio formats: MP3, AAC, WMA and others.
• Audio sampling rates: 8, 11.025, 12, 16, 22.05, 24, 32,
44.1, and 48 kHz
• Wide battery supply range 1.0V – 5.5V
• 12.288MHz crystal or 13MHz clock input
• System Power Management Features
• Low power consumption
3. Applications
• Audio platform for cellular phones
• Stand alone MP3 player and PDAs
• CD and DVD player
1.11, Feb. 2005
CONFIDENTIAL
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