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Information as of 2000-01-10
UDA1331H; Universal Serial Bus (USB) Audio Playback Peripheral (APP)
Check device status and availability before design in!
The UDA1331H is a stereo CMOS digital-to-analog
bitstream converter designed for USB-compliant audio
playback devices and multimedia audio applications.
The UDA1331H is an adaptive asynchronous sink USB
audio device with a continuous sampling frequency (fs )
range from 5 to 55 kHz. It contains a USB interface, an
embedded microcontroller and an Asynchronous
Digital-to-Analog Converter (ADAC).
The USB interface is the interface between the USB, the
ADAC and the microcontroller. The USB interface consists
of an analog front-end and a USB processor. The analog
front-end transforms the differential USB data to a digital
data stream. The USB processor buffers the input and
output data from the analog front-end and handles all
low-level USB protocols. The USB processor selects the
relevant data from the universal serial bus, performs an
extensive error detection and separates control
information (input and output) and audio information (input
only).
The control information becomes accessible at the
microcontroller. The audio information becomes available
at the digital I/O output or is fed directly to the ADAC.
The microcontroller handles the high-level USB protocols
translates the incoming control requests and manages the
user interface via General Purpose (GP) pins and an
I2PC-bus. The firmware for the microcontroller must be
located in an external (E)PROM.
The ADAC enables the wide and continuous range of input
sampling frequencies. By means of a Sample Frequency
Generator (SFG), the ADAC is able to reconstruct the
average sample frequency from the incoming audio
samples. The ADAC also performs the sound processing.
The ADAC consists of FIFO registers, a unique audio
feature processing DSP, the SFG, digital up-sampling
filters, a variable hold register, a Noise Shaper (NS) and a
Filter Stream DAC (FSDAC) with integrated filter and line
output drivers. The audio information is applied to the
ADAC via the USB processor or via the digital I/O input.
An external DSP can be used for adding extra sound
processing features via the digital I/O-bus.
The UDA1331H supports the standard I2PS-bus data input
format and the LSB-justified serial data input format with
word lengths of 16, 18 and 20 bits.
The wide dynamic range of the bitstream conversion
technique used in the UDA1331H guarantees a high audio
sound quality.
General
Sound processing
Document references
Page count File size (kB) Datasheet
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