CS4202 Datasheet, PDF (58/68 Pages) Cirrus Logic – Audio Codec 97 with headphone Amplifier

CS4202
VIDEO_L, VIDEO_R - Analog Video Audio Source, Inputs, Pins 16 and 17
These inputs form a stereo input pair to the CS4202. It is intended to be used for the audio signal
output of a video device. 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.
AUX_L, AUX_R - Analog Auxiliary Source, Inputs, Pins 14 and 15
These inputs form a stereo input pair to the CS4202. 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.
LINE_OUT_L, LINE_OUT_R - Analog Line-Level, Outputs, Pins 35 and 36
These signals are analog outputs from the stereo output mixer. The full-scale output voltage for each
output is nominally 1 V_RMS (sinusoidal). These outputs are internally biased at the Vrefout voltage
reference and require either AC-coupling to external circuitry or DC-coupling to a buffer op-amp biased
at the Vrefout voltage. These pins need a 680-1000 pF NPO capacitor attached to analog ground.
HP_OUT_L, HP_OUT_R - Analog Headphone, Outputs, Pins 39 and 41
These signals are analog outputs from the stereo output mixer. The full-scale output voltage for each
output is nominally 4 V_pp. These outputs are internally biased at the Vrefout voltage reference and
require AC-coupling to external circuitry. The HP_OUT pins can directly drive resistive loads as low as
32 Ω (such as standard consumer headphones). Capacitive loading must not exceed 200 pF per pin.
The outputs are short circuit protected for infinite duration.
HP_OUT_C - Analog Headphone Output Common Source, Input, Pin 40
This analog input is used to remove common mode noise from the headphone outputs. This is achieved
by biasing the headphone amplifier with the common mode noise on the headphone amplifier ground
plane. This pin should be AC-coupled through a 1 µF electrolytic capacitor to analog ground (AVss2)
near the headphone jack.
MONO_OUT - Analog Mono Line-Level, Output, Pin 37
This signal is an analog output from the stereo-to-mono mixer. The full-scale output voltage for this
output is nominally 1 V_RMS (sinusoidal). This output is internally biased at the Vrefout voltage reference
and requires either AC-coupling to external circuitry or DC-coupling to a buffer op-amp biased at the
Vrefout voltage. This pin needs a 680-1000 pF NPO capacitor attached to analog ground.
Analog Reference, Filter, and Configuration Pins
REFFLT - Internal Reference Voltage, Input, Pin 27
This signal is the voltage reference used internal to the CS4202. A 0.1 µF and a 2.2 µF ceramic
capacitor with short, wide traces must be connected to this pin. No other connections should be made
to this pin. Do not use an electrolytic 2.2 µF capacitor, use a type Z5U or Y5V ceramic capacitor.
Vrefout - Voltage Reference, Output, Pin 28
All analog inputs and outputs are centered around Vrefout, nominally 2.4 Volts. This pin may be used to
bias external amplifiers. It can also drive up to 5 mA of DC which can be used for microphone bias.
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