CS8415A-CZ Cirrus Logic Inc, CS8415A-CZ Datasheet - Page 15

• Manufacturer Part Number: CS8415A-CZ
• Description: Receiver IC
• Manufacturer: Cirrus Logic Inc

Specifications of CS8415A-CZ

• Driver Case Style: TSSOP
• No. Of Pins: 28
• Mounting Type: Surface Mount
• No. Of Channels: 7
• Peak Reflow Compatible (260 C): No
• Supply Voltage: 5V
• Supply Voltage Max: 5V
• Leaded Process Compatible: No
• Interface Type: Serial
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

rence will be reported in the receiver error register,
induce a pulse on RERR, invoke the occurrence of
a RERR interrupt, and affect the current audio sam-
ple according to the status of the HOLD bits. The
HOLD bits allow a choice of holding the previous
sample, replacing the current sample with zero
(mute), or not changing the current audio sample. If
a mask bit is set to 0, the error is masked, which im-
plies the following: its occurrence will not be re-
ported in the receiver error register, will not induce
a pulse on RERR or generate a RERR interrupt, and
will not affect the current audio sample. The QCRC
and CCRC errors do not affect the current audio
sample, even if unmasked.
5.4
The first 2 bytes of the Channel Status block are de-
coded into the Receiver Channel Status register.
The setting of the CHS bit in the Channel Status
Data Buffer Control register determines whether
the channel status decodes are from the A channel
(CHS = 0) or B channel (CHS = 1).
The PRO (professional) bit is extracted directly.
For consumer data, the COPY (copyright) bit is ex-
tracted, and the category code and L bits are decod-
ed to determine SCMS status, indicated by the
ORIG (original) bit. If the category code is set to
General on the incoming AES3 stream, copyright
will always be indicated even when the stream in-
dicates no copyright. Finally, the AUDIO bit is ex-
tracted and used to set an AUDIO indicator, as
described in the Non-Audio Auto-Detection sec-
tion below.
If 50/15 µs pre-emphasis is detected, the state of
the EMPH pin is adjusted accordingly.
The encoded channel status bits which indicate
sample word length are decoded according to
AES3-1992 or IEC 60958. Audio data routed to the
serial audio output port is unaffected by the word
length settings; all 24 bits are passed on as re-
ceived.
DS470PP3
Channel Status Data Handling
Appendix A describes the overall handling of
Channel Status and User data.
5.5
The incoming user data is buffered in a user acces-
sible buffer. Received User data may also be output
to the U pin under the control of a control register
bit. Depending on the clocking options selected,
there may not be a clock available to qualify the U
data output. Figure 9 illustrates the timing. If the
incoming user data bits have been encoded as Q-
channel subcode, the data is decoded and presented
in 10 consecutive register locations. An interrupt
may be enabled to indicate the decoding of a new
Q-channel block, which may be read through the
control port.
5.5.1
An AES3 data stream may be used to convey non-
audio data, thus it is important to know whether the
incoming AES3 data stream is digital audio or not.
This information is typically conveyed in channel
status bit 1 (AUDIO), which is extracted automati-
cally by the CS8415A. However, certain non-audio
sources, such as AC-3
not adhere to this convention, and the bit may not
be properly set. The CS8415A AES3 receiver can
detect such non-audio data. This is accomplished
by looking for a 96-bit sync code, consisting of
0x0000, 0x0000, 0x0000, 0x0000, 0xF872, and
0x4E1F. When the sync code is detected, an inter-
nal AUTODETECT signal will be asserted. If no
additional sync codes are detected within the next
4096 frames, AUTODETECT will be de-asserted
until another sync code is detected. The AUDIO bit
in the Receiver Channel Status register is the logi-
cal OR of AUTODETECT and the received chan-
nel status bit 1. If non-audio data is detected, the
data is still processed exactly as if it were normal
audio. It is up to the user to mute the outputs as re-
quired.
User Data Handling
Non-Audio Auto-Detection

or MPEG encoders, may
CS8415A
15