CS8420-CS Cirrus Logic Inc, CS8420-CS Datasheet - Page 24

• Manufacturer Part Number: CS8420-CS
• Description: Transceiver IC
• Manufacturer: Cirrus Logic Inc

Specifications of CS8420-CS

• Audio Control Type: Sample Rate Converter
• Supply Voltage Range: 4.75V To 5.25V
• Operating Temperature Range: -10°C To +70°C
• Audio Ic Case Style: SOIC
• No. Of Pins: 28
• Msl: MSL 2 - 1 Year
• Frequency Max: 108GHz
• Bandwidth: 20kHz
• Rohs Compliant: No
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

AES/SPDIF/IEC60958 Transmitter and Receiver
Components” on page 70.
9.6
Currently, the AES3 standard is being updated to
include options for 96 kHz sample rate operation.
One method is to double the frame rate of the cur-
rent format. This results in a 96 kHz sample rate,
stereo signal carried over a single twisted pair ca-
ble. An alternate method is where the 2 sub-frames
in a 48 kHz frame rate AES3 signal are used to car-
ry consecutive samples of a mono signal, resulting
in a 96 kHz sample rate stream. This allows older
equipment, whose AES3 transmitters and receivers
are not rated for 96 kHz frame rate operation, to
handle 96 kHz sample rate information. In this
“mono mode”, 2 AES3 cables are needed for stereo
data transfer. The CS8420 offers mono mode oper-
ation, both for the AES3 receiver and for the AES3
24
TCBL
in or out
VLRCK
TCBL
in or out
VLRCK
C, U, V
Input
U
Input
Mono Mode Operation
VLRCK is a virtual word clock, which may not exist, but is used to illustrate the CUV timing.
VLRCK duty cycle is 50%.
In stereo mode, VLRCK = AES3 frame rate. In mono mode, VLRCK = 2*AES3 frame rate
If the serial audio output port is in master mode, and TCBL is an output, and the SRC is not in use,
If the serial audio input port is in master mode, and TCBL is an input, and the SRC is not between
Otherwise, VLRCK needs to be externally created, if required
then VLRCK = OLRCK.
the serial audio input port and the AES3 transmitter, then VLRCK = ILRCK.
Figure 22. AES3 Transmitter Timing for C, U and V pin input data
Tsetup
CUV
AES3 Transmitter in Stereo Mode
AES3 Transmitter in Mono Mode
Thold
Tsetup
Tsetup = >7.5% AES3 frame time
Thold = 0
CUV
transmitter. Figure 23 shows the operation of mono
mode in comparison with normal stereo mode. The
receiver and transmitter sections may be indepen-
dently set to mono mode via the MMR and MMT
control bits.
The receiver mono mode effectively doubles Fsi
compared to the input frame rate. The clock output
on the RMCK pin tracks Fsi, and so is doubled in
frequency compared to stereo mode. In mono
mode, A and B sub-frames are routed to the SRC
inputs as consecutive samples.
When the transmitter is in mono mode, either A or
B SRC consecutive outputs are routed alternately
to A and B sub-frames in the AES3 output stream.
Which channel status block is transmitted is also
selectable.
For the AES3 input to serial audio port output data
flow, in receiver mono mode, then the receiver will
U
Thold
Tsetup = >15% AES3 frame time
Thold = 0
CUV
CS8420
DS245PP2
CUV
U