CS4227 Datasheet, PDF (31/36 Pages) Cirrus Logic – Six Channel, 20-Bit Codec

CS4227
LRCK - Left/Right Select Signal I/O
The Left/Right select signal. This signal has a frequency equal to the sample rate. The relationship of
LRCK to the left and right channel data depends on the selected format.
DEM - De-emphasis Control
When low, DEM controls the activation of the standard 50/15 us de-emphasis filter for either 32, 44.1 or
48 kHz sample rates. This pin is enabled by the DEM2-0 bits in the Auxiliary Port Control Byte.
OVL - Overload Indicator
This pin goes high if either of the stereo audio ADCs or the mono ADC is clipping.
Auxillary Digital Audio Signals
DATAUX - Auxiliary Data Input
DATAUX is the auxiliary audio data input line, usually connected to an external digital audio source.
LRCKAUX - Auxiliary Word Clock Input or Output
In auxiliary slave mode, LRCKAUX is a word clock (at Fs) from an external digital audio source. In
auxiliary master mode, LRCKAUX is a word clock output (at Fs) to clock an external digital audio
source.
SCLKAUX - Auxiliary Bit Clock Input or Output
In auxiliary slave mode, SCLKAUX is the serial data bit clock from an external digital audio source, used
to clock in data on DATAAUX. In auxiliary master mode, SCLKAUX is a serial data bit clock output.
HOLD - HOLD Control
This pin is sampled on the active edge of SCLKAUX. If it is high any time during the frame, DATAUX
data is ignored and the previous "good" sample is output to the serial output port.
Control Port Signals
SPI/I2C - Control Port Format
Setting this pin low configures the control port for the SPI interface; a high state configures the control
port for the I²C interface. The state of this pin sets the function of the control port input/output pins .
SCL/CCLK - Serial Control Interface Clock
SCL/CCLK is the serial control interface clock, and is used to clock control bits into and out of the
CS4227.
AD0/CS - Address Bit / Control Port Chip Select
In I²C^® mode, AD0 is a chip address bit. In SPI software control mode, CS is used to enable the control
port interface on the CS4227.
AD1/CDIN - Address Bit / Serial Control Data In
In I²C^® mode, AD1 is a chip address bit. In SPI software control mode, CDIN is the input data line for
the control port interface.
SDA/CDOUT - Serial Control Data Out
In I²C^® mode, SDA is the control data I/O line. In SPI software control mode, CDOUT is the output data
from the control port interface on the CS4227.
DS281PP2
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