- All features specified for Layer III in ISO/IEC
11172-3(MPEG 1 Audio)
- All features specified for Layer III in ISO/IEC
13818-3.2(MPEG 2 Audio)
- Lowersamplingfrequenciessyntaxextension,
(notspecifiedby ISO) called MPEG2.5
DECODES LAYER III STEREO CHANNELS,
DUALCHANNEL,SINGLECHANNEL
(MONO)
SUPPORTING ALL THE MPEG 1 & 2 SAMPLING FREQUENCIES AND THE EXTENSION TO MPEG 2.5:
48, 44.1, 32, 24, 22.05, 16, 12, 11. 025, 8 KHz
ACCEPTS MPEG 2.5 LAYER III ELEMENTARY COMPRESSED BITSTREAM WITH
DATA RATE FROM 8 Kbit/s UP TO 320 Kbit/s
DIGITALVOLUMECONTROL
DIGITALBASS& TREBLECONTROL
SERIALBITSTREAMINPUTINTERFACE
ANCILLARY DATA EXTRACTIONVIA I2C IN-
TERFACE.
SERIAL PCM OUTPUT INTERFACE (I
AND OTHERFORMATS)
PLL FOR INTERNAL CLOCK AND FOR OUT-
PUT PCMCLOCK GENERATION
LOW POWERCONSUMPTION:
85mW AT 2.4V
CRC CHECK AND SYNCHRONISATION ER-
ROR DETECTION WITH SOFTWARE INDICATORS
2
C CONTROLBUS
I
LOW POWER3.3V CMOSTECHNOLOGY
10 MHz, 14.31818 MHz, OR 14.7456 MHz
EXTERNAL INPUT CLOCK OR BUILT-IN INDUSTRY STANDARD XTAL OSCILLATOR
DIFFERENT FREQUENCIES MAY BE SUPPORTED UPON REQUESTTOSTM
APPLICATIONS
PC SOUNDCARDS
MULTIMEDIA PLAYERS
STA013BSTA013T
SO28
TQFP44
LFBGA64
2
S
ORDERING NUMBERS: STA013$ (SO28)
STA013T$ (TQFP44)
STA013B$ (LFBGA 8x8)
DESCRIPTION
The STA013 is a fully integrated high flexibility
MPEG Layer III Audio Decoder, capable of decoding Layer III compressedelementary streams,
as specifiedin MPEG1 and MPEG 2 ISO standards. The devicedecodes alsoelementarystreams
compressedby using low samplingrates,as specifiedbyMPEG2.5.
STA013 receives the input data through a Serial
Input Interface. The decoded signal is a stereo,
mono, or dual channel digital output that can be
sent directly to a D/A converter, by the PCM Output Interface. This interface is software programmable to adapt the STA013 digital output to the
most common DACs architectures used on the
market.
The functional STA013 chip partitioning is describedin Fig.1.
Power Supply-0.3 to 4V
Voltage on Input pins-0.3 to VDD+0.3V
Voltage on output pins-0.3 to VDD+0.3V
Storage Temperature-40 to +150°C
Operative ambient temp-20 to +85°C
129B5VDD_1Supply Voltage
230B4VSS_1Ground
331A4SDAI/Oi
432B3SCLII
534A1SDIIReceiver Serial DataCMOS Input Pad Buffer
636B2SCKRIReceiver Serial ClockCMOS Input Pad Buffer
738D4BIT_ENIBit EnableCMOSInputPad Buffer
840D1SRC_INTIInterrupt Line For S.R. ControlCMOS Input Pad Buffer
942E2SDOOTransmitter SerialData (PCM
1044F2SCKTOTransmitter Serial ClockCMOS 4mA Output Drive
112H1LRCKTOTransmitter Left/Right ClockCMOS 4mA Output Drive
123H3OCLKI/OOversampling Clock for DACCMOS Input Pad Buffer
135F3VSS_2Ground
146E4VDD_2Supply Voltage
157G4VSS_3Ground
168G5VDD_3Supply Voltage
1710F5PVDDPLL Power
1811G6PVSSPLL Ground
1912G7FILTOPLL Filter Ext. Capacitor Conn.
2013G8XTOOCrystal OutputCMOS 4mA Output Drive
2115F7XTIICrystal Input (Clock Input)Specific Level Input Pad
2219E7VSS_4Ground
2321C8VDD_4Supply Voltage
2422D7TESTENITest EnableCMOSInputPad Buffer
2524A7SCANENIScan EnableCMOS Input Pad Buffer
2625B6RESETISystem ResetCMOSInputPad Buffer
2726A5VSS_5Ground
2827C5OUT_CLK/
DATA_REQ
Note: SRC_INT signal is used by STA013 internalsoftware inBroadcast Modeonly;in Multimedia mode SRC_INT must be connected to
In functionalmodeTESTEN must be connected to VDD,SCANEN to ground.
V
DD
2
C Serial Data + AcknowledgeCMOS Input Pad Buffer
CMOS 4mA Output Drive
2
C Serial ClockCMOS Input Pad Buffer
withpull up
CMOS 4mA Output Drive
Data)
CMOS 4mA Output Drive
(see paragraph 2.1)
withpull up
withpull up
OBuffered Output Clock/
CMOS 4mA Output Drive
Data Request Signal
4/38
STA013 - STA013B - STA013T
1. ELECTRICALCHARACTERISTICS:VDD=2.4V±0.3V;T
amb
= 0 to 70°C;Rg = 50Ωunlessotherwise
specified
DC OPERATINGCONDITIONS
SymbolParameterValue
V
T
Power Supply Voltage2.7 to 3.6V
DD
Operating Junction Temperature-20 to 125°C
j
GENERAL INTERFACE ELECTRICALCHARACTERISTICS
SymbolParameterTest ConditionMin.Typ.Max.UnitNote
I
IL
Low Level Input Current
Vi= 0V-1010µA1
Without pull-up device
I
IH
High Level Input Current
Vi=VDD= 3.6V-1010
A1
µ
Without pull-up device
V
esd
Note 1: The leakage currents are generally very small, < 1nA. The value given here is a maximum thatcan occur after an electrostatic stress
on the pin.
Note 2: Human Body Model.
Electrostatic ProtectionLeakage < 1µA2000V2
DC ELECTRICAL CHARACTERISTICS
SymbolParameterTest ConditionMin.Typ.Max.UnitNote
V
IL
V
IH
V
ol
V
oh
Low Level Input Voltage0.2*V
High Level Input Voltage0.8*VDDV
Low Level Output VoltageIol= Xma0.4VV1, 2
High Level Output Voltage0.85*V
DD
V
DD
V1,2
Note 1: Takes intoaccount 200mV voltage drop in both supply lines.
Note 2: X is the source/sink current under worst case conditions and is reflected in the name of the I/O cell according to the drive capability.
The STA013 input clock is derivated from an external source or from a industry standard crystal
oscillator, generating input frequencies of 10,
14.31818 or 14.7456 MHz.
Other frequencies may be supported upon request to STMicroelectronics. Each frequency is
supported by downloading a specific configuration file, providedby STM
XTI is an input Pad with specific levels.
SymbolParameterTest ConditionMin.Typ.Max.Unit
V
IL
V
IH
Low Level Input VoltageVDD-1.8V
High Level Input VoltageVDD-0.8V
CMOS compatibility
The XTI pad low and high levels are CMOS compatible; XTI pad noise margin is better than typical
CMOS pads.
TTL compatibility
The XTI padlow levelis compatiblewith TTL while the high level is not compatible(for example if V
DD =
3V TTL min high level = 2.0V whileXTI min high level = 2.2V)
6/38
Figure 5. MPEG DecoderInterfaces.
STA013 - STA013B - STA013T
µP
DATA_REQ
SDI
DATA
SOURCE
D98AU912
SCKR
BIT_EN
Figure 6. SerialInput Interface Clocks
SDI
SCKR
SCKR
XTO
XTIFILT
PLL
MPEG
DECODER
SERIAL AUDIO INTERFACE
RXTX
IIC
SCLSDA
IIC
DATA IGNORED
SDO
SCKT
LRCKT
DAC
OCLK
SCLK_POL=0
SCLK_POL=4
BIT_EN
D98AU968A
2.2 - SerialInput Interface
STA013 receives the input data (MSB first)
thought the Serial Input Interface (Fig.5). It is a
serial communication interface connected to the
SDI (Serial Data Input) and SCKR (Receiver Serial Clock).
The interface can be configured to receive data
sampled on both rising and falling edge of the
SCKR clock.
The BIT_EN pin, when set to low, forces the bitstream input interface to ignore the incoming
N
data. For proper operation Bit-E
line shold be
toggled only when SCR is stable low (for both
SCLK_POL configuration) The possible configurations are described in Fig. 6.
DATA IGNOREDDATA VALID
2.3 - PLL& ClockGeneratorSystem
When STA013 receives the input clock, as described in Section 2.1, and a valid layer III input
bit stream, the internal PLL locks, providing to the
DSP Core the master clock (DCLK), and to the
Audio Output Interface the nominal frequenciesof
the incoming compressedbit stream.The STA013
PLLblockdiagramisdescribedinFigure7.
The audio sample rates are obtained dividing the
oversampling clock (OCLK) by software programmable factors. The operation is done by STA013
embedded software and it is transparent to the
user.
The STA013 PLL can drive directly most of the
commercial DACs families, providing an over
sampling clock, OCLK, obtained dividingthe VCO
frequencywith a softwareprogrammabledividers.
7/38
STA013 - STA013B - STA013T
Figure 7. PLL and Clocks GenerationSystem
XTI
N
PFDCP
M
FRAC
Update FR AC
Switching
Circuit
2.4 - PCM Output Interface
The decoded audio data are output in serial PCM
format. The interface consists of the followingsignals:
SDOPCM SerialData Output
SCKTPCMSerial Clock Output
LRCLKLeft/RightChannel SelectionClock
The output samples precision is selectable from
Figure 8. PCM Output Formats
16 SCLK Cycles
LRCKT
16 SCLK Cycles
R
CC
VCO
Disable PLL
OCLK
X
XTI2OCLK
DCLK
S
XTI2DSPCLK
16 to 24 bits/word, by settingthe output precision
with PCMCONF (16, 18, 20 and 24 bits mode)
register. Data can be output either with the most
significant bit first (MS) or least significant bit first
(LS), selected by writing into a flag of the
PCMCONFregister.
Figure 8 gives a description of the several
STA013PCM Output Formats.
The sample rates set decoded by STA013 is describedin Table1.
16 SCLK Cycles
16 SCLK Cycles
16 SCLK Cycles
SDO
SDO
M
S
L
S
M
L
S
S
L
M
S
S
32 SCLK Cycles
LRCKT
SDO
SDO
SDO
SDO
M
L
S
S
M
0
S
L
M
0
S
S
M
S
32 SCLK Cycles
M
S
L
S
M
0
00
S
L
MSBMSBMSBMSB
S
Table 1: MPEG SamplingRates (KHz)
MPEG 1MPEG 2MPEG 2.5
482412
44.122.0511.025
32168
L
M
S
S
L
M
S
S
32 SCLK Cycles
M
L
S
S
M
L
S
S
PCM_ORD = 0
L
S
PCM_PRECis 16 bit mode
PCM_ORD = 1
M
S
PCM_PRECis 16 bit mode
32 SCLK Cycles
32 SCLK Cycles
L
00
S
L
M
S
S
L
S
L
M
S
S
L
M
S
S
M
00
S
M
0
S
MSL
M
0
L
S
L
00
S
S
L
S
S
M
0
S
L
M
0
S
S
M
S
PCM_FORMAT = 1
0
PCM_DIFF = 1
PCM_FORMAT = 0
L
S
PCM_DIFF = 0
PCM_FORMAT = 0
PCM_DIFF = 1
PCM_FORMAT = 1
L
S
PCM_DIFF = 1
8/38
STA013 - STA013B - STA013T
2.5 - STA013Operation Mode
The STA013 can work in two different modes,
called Multimedia Mode and BroadcastMode.
In Multimedia Mode, STA013 decodes the in-
coming bitstream, acting as a master of the data
communicationfrom the source to itself.
This control is done by a specific buffer management, controlled by STA013embeddedsoftware.
The data source, by monitoring the DATA_REQ
line, send to STA013 the input data, when the
signal ishigh (default configuration).
Thecommunication isstopped whenthe
DATA_REQline is low.
In this mode the fractional part of the PLL is disabled and the audio clocks are generated at
nominal rates. Fig. 9 describes the default
DATA_REQsignalbehaviour.
Programming STA013 it is possible to invert the
polarityoftheDATA_REQline(register
REQ_POL).
Figure 9.
SOURCE STOPS TRANSMITTING DATASOURCE STOPS TRANSMITTING DATA
DATA_REQ
SOURCE SEND DATA TO STA013
D98AU913
the configuration register of the device. The DAC
connected to STA013 can be initialised during
this mode (set MUTE to 1).
PLAYMUTEClock State PCM Output
X0Not Running0
X1Running0
Init Mode
”PLAY” and ”MUTE” changes are ignored in this
mode. The internal state of the decoder will be
updated only when the decoder changes from the
state ”init” to the state ”decode”. The ”init” phase
ends when the first decoded samples are at the
output stage of the device.
Decode Mode
This mode is completely described by the following table:
PLAYMUTE Clock State
00Not Running0No
01Running0No
10RunningDecoded
11Running0Yes
PCM
Output
Samples
Decoding
Yes
In Broadcast Mode, STA013 works receiving a
bitstream with the input speed regulated by the
source. In this configuration the source has to
guarantee that the bitrate is equivalent to the
nominal bitrate of the decoded stream.
To compensate the differencebetween the nominal and the real sampling rates, the STA013 embedded software controls the fractional PLL operation. Portable or Mobile applications need
normally to operate in Broadcast Mode. In both
modes the MPEG Synchronisation is automatic
and transparent to the user. To operate in Multimedia mode, the STA013, pin nr. 8, SCR-INT
must be connected to VDD on the application
board.
2.6 - STA013Decoding States
There are three different decoder states: Idle,
Init, and Decode. Commands to change the de-
coding states are described in the STA013 I
2
C
registers description.
Idle Mode
In this mode the decoder is waiting for the RUN
command. This mode should be used to initialise
3-I2C BUS SPECIFICATION
The STA013 supports the I
2
C protocol. This protocol defines any device that sends data on to the
bus as a transmitter and any device that reads
the data as a receiver. The device that controls
the data transfer is known as the master and the
others as the slave. The master always starts the
transfer and provides the serialclock forsynchronisation. The STA013 is always a slave device in
all its communications.
3. 1 - COMMUNICATIONPROTOCOL
3.1.0 - Data transition or change
Data changes on the SDA line must only occur
when the SCL clock is low. SDA transition while
the clock is high are used to identify START or
STOP condition.
3.1.1 - Start condition
START is identified by a high to low transition of
the data bus SDA signal while the clock signal
SCL is stable in the high state.
A START condition must precede any command
fordatatransfer.
9/38
STA013 - STA013B - STA013T
3.1.2 - Stop condition
STOP is identified by low to high transition of the
data bus SDA signal while the clock signal SCL is
stable in the high state. A STOP condition terminates communications between STA013 and the
bus master.
3.1.3 - Acknowledge bit
An acknowledgebit is used toindicate a successful data transfer. The bus transmitter, either master or slave, releases the SDA bus after sending
8 bit of data.
During the 9th clock pulse the receiver pulls the
SDA bus low to acknowledgethe receipt of 8 bits
of data.
3.1.4 - Data input
During the data input the STA013 samples the
SDA signal on the rising edge of the clock SCL.
For correct device operation the SDA signal has
to be stable during the rising edge of the clock
and the data can change only when the SCL line
is low.
3.2 - DEVICEADDRESSING
To start communication between the master and
the STA013, the master must initiate with a start
condition. Following this, the master sends onto
the SDA line 8 bits (MSB first) corresponding to
the device select address and read or write
mode.
Figure 10. Write Mode Sequence
The 7 most significant bits are the device address
identifier, corresponding to the I
2
C bus definition.
For the STA013these are fixed as 1000011.
The 8th bit (LSB) is the read or write operation
RW, this bit is set to 1 in read mode and 0 for
write mode. After a STARTcondition the STA013
identifies on the bus the device address and, if a
match is found, it acknowledgesthe identification
on SDA bus during the 9th bittime. The following
byte after the device identification byte is the internal space address.
3.3 - WRITEOPERATION(see fig. 10)
Following a START condition the master sends a
deviceselectcode with the RW bit set to 0.
The STA013 acknowledges this and waits for the
byte ofinternal address.
After receiving the internal bytes address the
STA013again responds with an acknowledge.
3.3.1 - Byte write
In the bytewrite mode the mastersends one data
byte, this is acknowledged by STA013. The master then terminates the transfer by generating a
STOP condition.
3.3.2 - Multibytewrite
The multibyte write mode can start from any internal address. The transfer is terminated by the
master generatinga STOPcondition.
BYTE
WRITE
MULTIBYTE
WRITE
START
STARTRW
DEV-ADDR
DEV-ADDR
Figure 11. Read Mode Sequence
ACK
CURRENT
ADDRESS
RANDOM
ADDRESS
SEQUENTIAL
CURRENT
SEQUENTIAL
RANDOM
10/38
READ
READ
READ
READ
DEV-ADDR
START
DEV-ADDR
STARTRW
START
STARTRW
DEV-ADDR
DEV-ADDR
RW=
HIGH
DATA
RW
ACK
SUB-ADDR
ACK
DATA
ACK
SUB-ADDR
ACK
RW
ACK
NO ACK
ACK
STARTRW
ACK
ACK
STARTRW
SUB-ADDR
SUB-ADDR
STOP
DATA
DEV-ADDR
DEV-ADDR
ACK
ACK
ACK
ACK
ACK
DATA IN
DATA IN
DATA
DATA
DATA
ACK
ACK
STOP
NO ACK
NO ACK
ACK
D98AU825B
STOP
STOP
DATA
DATA IN
ACK
ACKNO ACK
D98AU826A
STOP
DATA
STOP
STA013 - STA013B - STA013T
3.4 - READOPERATION(see Fig. 11)
3.4.1 - Currentbyte addressread
The STA013 has an internal byte address
counter. Each time a byte is written or read, this
counter is incremented.
For the current byte address read mode, following a START condition the master sends the device addresswith the RW bit setto 1.
The STA013 acknowledges this and outputs the
byte addressed by the internal byte address
counter. The master does not acknowledge the
received byte, but terminates the transfer with a
STOP condition.
3.4.2 - Sequentialaddress read
This mode can be initiated with either a current
address read or a random address read. However in this case the master does acknowledge
the data byte output and the STA013 continues to
output the next byte in sequence.
To terminate the streams of bytes the master
does not acknowledgethe last received byte, but
terminatesthe transfer with a STOP condition.
The output data stream is from consecutive byte
addresses, with the internal byte address counter
automaticallyincrementedafter one byte output.
2
4-I
C REGISTERS
The following table gives a description of the
MPEGSource Decoder (STA013)register list.
The first column (HEX_COD) is the hexadecimal
code for the sub-address.
The second column (DEC_COD) is the decimal
code.
The third column (DESCRIPTION) is the description of the informationcontained in the register.
The fourth column (RESET) inidicate the reset
value if any. When no reset value is specifyed,
the default is ”undefined”.
The fifth column (R/W) is the flag to distinguish
register ”read only” and ”read and write”, and the
useful size of the register itself.
Each register is 8 bitwide. The master shall operate readingor writing on 8 bits only.