msm7732 ETC-unknow, msm7732 Datasheet - Page 5

• Manufacturer Part Number: msm7732
• Description: Audio Codec
• Manufacturer: ETC-unknow

¡ Semiconductor
PIN FUNCTIONAL DISCRIPTION
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 and inputs 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 W load. AOUT+ and AOUT–
are differential analog signal outputs which can directly drive 32 W load. Refer to Figure 1.
These outputs are in a high impedance state during power-down mode.
VI
10 mF
Sounder output signal
V
O
=V
VFRO
+
–
(R3/R4) ¥ 2
R1
Figure 1 Analog Input/Output Interface
R3
R4
0.1 mF
R2
AIN–
AIN+
GSX
AOUT+
AOUT–
SG
PWI
VFRO
SAO
–
+
–1
–
+
V
GSX
=VI (R2/R1)
V
REF
DAC
MSM7732
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