CS4222 Datasheet, PDF (9/26 Pages) Cirrus Logic – 20-Bit Stereo Audio Codec with Volume Control

CS4222
FUNCTIONAL DESCRIPTION
Overview
The CS4222 has 2 channels of 20-bit analog-to-
digital conversion and 2 channels of 20-bit
digital-to-analog conversion. All ADCs and
DACs are delta-sigma converters. The DAC out-
puts have adjustable output attenuation
implemented in 0.5 dB step resolution. The de-
vice also includes a soft mute function and
digital de-emphasis for 32, 44.1, and 48 kHz.
Digital audio data for the DACs and from the
ADCs is communicated over separate serial
ports. This allows concurrent writing to and
reading from the device. Control for the func-
tions available on the CS4222 are communicated
over a serial microcontroller interface. Figure 1
shows the recommended connection diagram for
the CS4222.
The device can be operated with or without the
control port interface. Additional functions are
available when the control port interface is used
as outlined in Table 1.
Control Port
Volume control
Adjustable Mute ramp rate
Enable zero crossing detect
Disable mute on zero input
De-emphasis
Mute DAC outputs
ADC Input Peak Level
Detect
16, 18, 20 bit Interface
Individual ADC/DAC power
down
Cal on command
High pass enable/disable
Stand-alone
-
Fixed Mute ramp rate
Disabled
Enabled
De-emphasis
Mute DAC outputs
-
20 bit I²S Interface
Codec power down
Cal on power-up
High pass enabled
Table 1. Control Port vs. Stand-alone
Analog Inputs
Line Level Inputs
AINR-, AINR+, AINL-, and AINL+ are the dif-
ferential line level input pins (See Figure 1).
Figure 2 shows an AC coupled optional input
buffer which combines level shifting with single-
ended to differential conversion. Analog inputs
must be DC coupled into the CS4222 with a
2.3V common mode input voltage. Any DC off-
Figure 2. Optional Line Input Buffer
DS236PP3
9