CS4202-JQZR Cirrus Logic Inc, CS4202-JQZR Datasheet - Page 51

• Manufacturer Part Number: CS4202-JQZR
• Description: IC AC97 W/Headphone Amplifier
• Manufacturer: Cirrus Logic Inc
• Type: Audio Codec '97r

Specifications of CS4202-JQZR

• Data Interface: Serial
• Resolution (bits): 24 b
• Number Of Adcs / Dacs: 1 / 1
• Sigma Delta: Yes
• Dynamic Range, Adcs / Dacs (db) Typ: 90 / 90
• Voltage - Supply, Analog: 4.75 V ~ 5.25 V
• Voltage - Supply, Digital: 4.75 V ~ 5.25 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 48-TQFP, 48-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Mic Volume Register (Index 0Eh) the pre-amplifier
gain can be set to 0 dB, 10 dB, 20 dB, or 30 dB.
10.1.4 PC Beep Input
The PC_BEEP input is useful for mixing the output
of the “beeper” (timer chip), provided in most PCs,
with the other audio signals. When the CS4202 is
held in reset, PC_BEEP is passed directly to the line
output. This allows the system sounds or “beeps” to
be available before the AC ’97 interface has been ac-
tivated. Figure 21 illustrates a typical input circuit for
the PC_BEEP input. If PC_BEEP is driven from a
CMOS gate, the 4.7 kΩ resistor should be tied to an-
alog ground instead of +5VA. Although this input is
described for a low-quality “beeper”, it is of the same
high-quality as all other analog inputs and may be
used for other purposes.
DS549PP2
PC-BEEP-BUS
AGND
1.5 kΩ
2.2 kΩ
Figure 20. Microphone Input
Figure 21. PC_BEEP Input
+5VA
AGND if CMOS Source
+5VA (Low Noise) or
100 Ω
10 µ F
47 kΩ
ELEC
2.7 nF
+
X7R
AGND
AGND
AGND
4.7 kΩ
0.1 µ F
X7R
0.1 µ F
0.1 µ F
X7R
X7R
PC_BEEP
MIC1/MIC2
10.1.5 Phone Input
One application of the PHONE input is to interface
to the output of a modem analog front end (AFE) de-
vice so that modem dialing signals and protocol ne-
gotiations may be monitored through the audio
system. Figure 22 shows a design for a modem con-
nection where the output is fed from the CS4202
MONO_OUT pin through a divider. The divider ra-
tio shown does not attenuate the signal, providing an
output voltage of 1 V
is desired, the resistors can be replaced with appro-
priate values, as long as the total load on the output
is kept greater than 10 kΩ. The PHONE input is di-
vided by 6 dB to accommodate a line-level source of
2 V
10.2 Analog Outputs
The analog output section provides a stereo, a head-
phone, and a mono output. The MONO_OUT,
LINE_OUT_L, and LINE_OUT_R pins require
680 pF to 1000 pF NPO dielectric capacitors be-
tween the corresponding pin and analog ground.
Each analog output is DC-biased up to the Vrefout
voltage signal reference, nominally 2.4 V. This re-
quires the outputs be AC-coupled to external circuit-
ry (AC loads must be greater than 10 kΩ for the line
output or 32 Ω for the headphone output). The head-
phone coupling capacitors should be 220 µF or great-
er to minimize low frequency roll-off.
10.2.1 Stereo Outputs
The LINE_OUT and HP_OUT stereo outputs de-
pend on the configuration of the HPCFG pin. As
shown in Figure 23, if the HPCFG pin is left floating,
RMS
MONO_OUT
PHONE
.
Figure 22. Modem Connection
47 kΩ
6.8 kΩ
0 Ω
RMS
AGND
. If a lower output voltage
1.0 µ F
6.8 kΩ
1.0 µ F
AGND
1000 pF
CS4202
PHONE
MONO_OUT
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