CS4201 Datasheet, PDF (57/68 Pages) Cirrus Logic – CrystalClear Audio Codec 97 with headphone Amplifier

CS4201
Audio I/O Pins
PC_BEEP - Analog Mono Source, Input, Pin 12
The PC_BEEP input is intended to allow the PC system POST (Power On Self-Test) tones to pass
through to the audio subsystem. The PC_BEEP input has two connections: the first connection is to the
analog output mixer, the second connection is directly to the LINE_OUT stereo outputs (if HPCFG is
floating) or through the headphone amplifier to the HP_OUT pins (if HPCFG is tied low). While the
RESET# pin is actively being asserted to the CS4201, the PC_BEEP bypass path to the LINE_OUT
outputs is enabled. While the CS4201 is in normal operation mode with RESET# de-asserted,
PC_BEEP is a monophonic source to the analog output mixer. The maximum allowable input is 1 V_RMS
(sinusoidal). This input is internally biased at the Vrefout voltage reference and requires AC-coupling to
external circuitry. If this input is not used, it should be connected to the Vrefout pin or AC-coupled to
analog ground.
PHONE - Analog Mono Source, Input, Pin 13
This analog input is a monophonic source to the output mixer. It is intended to be used as a modem
subsystem input to the audio subsystem. The maximum allowable input is 1 V_RMS (sinusoidal). This
input is internally biased at the Vrefout voltage reference and requires AC-coupling to external circuitry.
If this input is not used, it should be connected to the Vrefout pin or AC-coupled to analog ground.
MIC1 - Analog Mono Source, Input, Pin 21
This analog input is a monophonic source to the analog output mixer. It is intended to be used as a
desktop microphone connection to the audio subsystem. The CS4201 internal mixer’s microphone input
is MUX selectable with either MIC1 or MIC2 as the input. The maximum allowable input is 1 V_RMS
(sinusoidal). This input is internally biased at the Vrefout voltage reference and requires AC-coupling to
external circuitry. If this input is not used, it should be connected to the Vrefout pin or AC-coupled to
analog ground.
MIC2 - Analog Mono Source, Input, Pin 22
This analog input is a monophonic source to the analog output mixer. It is intended to be used as an
alternate microphone connection to the audio subsystem. The CS4201 internal mixer’s microphone input
is MUX selectable with either MIC1 or MIC2 as the input. The maximum allowable input is 1 V_RMS
(sinusoidal). This input is internally biased at the Vrefout voltage reference and requires AC-coupling to
external circuitry. If this input is not used, it should be connected to the Vrefout pin or AC-coupled to
analog ground.
LINE_IN_L, LINE_IN_R - Analog Line Source, Inputs, Pins 23 and 24
These inputs form a stereo input pair to the CS4201. The maximum allowable input is 1 V_RMS
(sinusoidal). These inputs are internally biased at the Vrefout voltage reference and require AC-coupling
to external circuitry. If these inputs are not used, they should both be connected to the Vrefout pin or
AC-coupled to analog ground.
CD_L, CD_R - Analog CD Source, Inputs, Pins 18 and 20
These inputs form a stereo input pair to the CS4201. It is intended to be used for the Red Book CD
audio connection to the audio subsystem. The maximum allowable input is 1 V_RMS (sinusoidal). These
inputs are internally biased at the Vrefout voltage reference and require AC-coupling to external circuitry.
If these inputs are not used, they should both be connected to the Vrefout pin or AC-coupled to analog
ground.
CD_GND - Analog CD Common Source, Input, Pin 19
DS483PP3
57