msm7732a Oki Semiconductor, msm7732a Datasheet - Page 6

• Manufacturer Part Number: msm7732a
• Description: Audio Codec
• Manufacturer: Oki Semiconductor

PIN FUNCTIONAL DESCRIPTION
AIN+, AIN–, GSX
Transmit analog inputs and the output for transmit gain adjustment.
AIN– connects to inverting input of the internal transmit amplifier. AIN+ connects to non-inverting input of the
internal transmit amplifier. GSX connects to the internal transmit amplifier output. Refer to Figure 1 for gain
adjustment.
VFRO, SAO, AOUT+, AOUT–, PWI
Receive analog outputs and the outputs for receive gain adjustment.
VFRO is the receive filter output for the voice signal. SAO is the receive filter output for an acoustic component of
the sound tone. SAO can directly drive 32
which can directly drive a 32
OKI Semiconductor
0.1 µF
Vi
load. Refer to Figure 1.
Figure 1 Analog Input/Output Interface
10 µF
Sounder output signal
+
–
Vo = V
C1
VFRO
R1
load. AOUT+ and AOUT– are differential analog signal outputs
(R3/R4) 2
R3
R4
R2
GSX
AIN–
AIN+
AOUT–
SG
AOUT+
PWI
VFRO
SAO
+
–
–1
Transmit Gain:
V
GSX
VREF
/Vi
to ENCODER
Conv.
D/A
FEDL7732A-01-01
MSM7732A-01
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