INTEGRATED CIRCUITS
DATA SHEET
UDA1321
Universal Serial Bus (USB)
Digital-to-Analog Converter (DAC)
Preliminary specification
Supersedes data of 1998 May 12
File under Integrated Circuits, IC01
1998 Oct 06
Philips Semiconductors
Preliminary specification
Universal Serial Bus (USB)
Digital-to-Analog Converter (DAC)
UDA1321
FEATURES
General
•
Universal Serial Bus (USB) stereo Digital-to-Analog
Converter (DAC) system with adaptive (5 to 55 kHz)
20-bits digital-to-analog conversion and filtering
•
USB-compliant audio and Human Interface Device
(HID)
•
Supports 12 Mbits/s full-speed serial data transmission
•
Supports multiple audio data formats (8, 16 and 24 bits)
•
Supports headphone and line output
•
Fully automatic ‘Plug-and-Play’ operation
•
High linearity
•
Wide dynamic range
•
Superior signal-to-noise ratio (typical 95 dB)
•
Low total harmonic distortion (typical 90 dB)
•
3.3 V power supply
•
Efficient power management
•
Low power consumption
•
On-chip master clock oscillator, only an external crystal
is required
•
Partly programmable USB descriptors and configuration
via I
2
C-bus.
Sound processing
•
Separate digital volume control for left and right channel
•
Soft mute
•
Digital bass and treble tone control
•
External Digital Sound Processor (DSP) option possible
via standard I
2
S-bus or Japanese digital I/O format
•
Selectable clipping prevention
•
Selectable Dynamic Bass Boost (DBB)
•
On-chip digital de-emphasis.
Document references
•
“USB Specification”
•
“USB Common Class Specification”
•
“USB Device Class Definition for Audio Devices”
•
“Device Class Definition for Human Interface Devices
(HID)”
•
“USB HID Usage Table”.
APPLICATIONS
•
USB monitors
•
USB speakers
•
USB headsets
•
USB telephone/answering machines
•
USB links in consumer audio devices.
GENERAL DESCRIPTION
The UDA1321 is a stereo CMOS digital-to-analog
bitstream converter designed for USB-compliant audio
playback devices and multimedia audio
applications.The UDA1321 is an adaptive asynchronous
sink USB audio device with a continuous sampling
frequency (f
s
) 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).
1998 Oct 06
2
Philips Semiconductors
Preliminary specification
Universal Serial Bus (USB)
Digital-to-Analog Converter (DAC)
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
I
2
C-bus.
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.
UDA1321
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 UDA1321 supports the standard I
2
S-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 UDA1321 guarantees a high audio
sound quality.
QUICK REFERENCE DATA
SYMBOL
Supplies
V
DD
I
DD(tot)
I
DD(ps)
supply voltage
total supply current
supply current in power-save
mode
total harmonic
distortion-plus-noise to signal
ratio
note 1
note 3
3.0
−
−
3.3
50
18
3.6
−
−
V
mA
mA
PARAMETER
CONDITIONS
MIN.
TYP.
MAX.
UNIT
Dynamic performance DAC
THD
+
N
----------------------
-
S
f
s
= 44.1 kHz; R
L
= 5 kΩ
at input signal of 1 kHz (0 dB)
−
−
at input signal of 1 kHz (−60 dB)
−
−
90
−
−90
(2)
−80
0.0032 0.01
−30
(2)
−20
3.2
95
0.66
10
−
−
dB
%
dB
%
dBA
V
S/N
bz
V
o(FS)(rms)
signal-to-noise ratio at bipolar
zero
full-scale output voltage
(RMS value)
audio sample input frequency
operating ambient temperature
A-weighted at code 0000H
V
DD
= 3.3 V
General characteristics
f
i(sample)
T
amb
Notes
1. V
DD
is the supply voltage on pins V
DDA
, V
DDE
, V
DDI
and V
DDX
. V
SS
is the ground on pins V
SSA
, V
SSE
, V
SSI
and V
SSX
.
All V
DD
and V
SS
pins must be connected to the same supply or ground respectively.
2. The audio information from the USB interface is fed directly to the ADAC.
3. The power-save mode (power management) is not supported in the UDA1321/N101;
see Chapter “USB-DAC UDA1321/N101 (Firmware sw 2.1.1.7)”.
5
0
−
25
55
70
kHz
°C
1998 Oct 06
3
Philips Semiconductors
Preliminary specification
Universal Serial Bus (USB)
Digital-to-Analog Converter (DAC)
ORDERING INFORMATION
PACKAGE
TYPE NUMBER
NAME
UDA1321H/N101
UDA1321T/N101
UDA1321PS/N101
QFP64
SO28
SDIP32
DESCRIPTION
plastic quad flat package; 64 leads (lead length 1.95 mm);
body 14
×
20
×
2.8 mm
plastic small outline package; 28 leads; body width 7.5 mm
plastic shrink dual in-line package; 32 leads (400 mil)
UDA1321
VERSION
SOT319-2
SOT136-1
SOT232-1
1998 Oct 06
4
Philips Semiconductors
Preliminary specification
Universal Serial Bus (USB)
Digital-to-Analog Converter (DAC)
BLOCK DIAGRAM
handbook, full pagewidth
UDA1321
D+
D−
TC
RTCB
SHTCB
TEST
CONTROL
BLOCK
ANALOG FRONT-END
SCL
SDA
EA
USB-PROCESSOR
PSEN
ALE
P2.0
GP4/BCKO
GP3/WSO
GP2/DO
GP1/DI
GP0/BCKI
GP5/WSI
MICRO-
CONTROLLER
DIGITAL I/O
P2.4
P2.5
P2.6
P2.7
P0.0
FIFO REGISTERS
fs
SAMPLE
FREQUENCY
GENERATOR
AUDIO FEATURE
PROCESSING DSP
fs
UP-SAMPLE FILTERS
64fs
VSSX
XTAL1
XTAL2
VDDX
OSC
TIMING
128fs
3rd-ORDER
NOISE SHAPER
VARIABLE HOLD REGISTER
VDDE
VSSE
P0.1
P0.2
P0.3
P0.4
P0.5
P0.6
P0.7
P2.1
P2.2
P2.3
UDA1321H
UDA1321T
UDA1321PS
VSSI
VDDI
VDDO
VSSO
VDDA
VSSA
VOUTL
LEFT
DAC
RIGHT
DAC
VOUTR
REFERENCE
VOLTAGE
Vref
MGM839
Fig.1 Block diagram.
1998 Oct 06
5
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