¡ Semiconductor
MSM7702-01/02/03
PIN AND FUNCTIONAL DESCRIPTIONS
AIN+, AIN–, GSX
Transmit analog input and transmit level adjustment.
AIN+ is a non-inverting input to the op-amp; AIN– is an inverting input to the op-amp; GSX is
connected to the output of the op-amp and is used to adjust the level, as shown below.
When not using AIN– and AIN+, connect AIN– to GSX and AIN+ to SG. During power saving
and power down modes, the GSX output is at AG voltage.
1) Inverting input type
R1 : variable
R2 > 20 kW
C1 > 1/(2 ¥ 3.14 ¥ 30 ¥ R1)
GSX
AIN–
AIN+
SG
C1
R2
–
+
Analog input
R1
Gain = R2/R1 £ 10
2) Non inverting input type
C2
R3 > 20 kW
AIN+
AIN–
GSX
+
–
Analog input
R4 > 20 kW
R5 > 50 kW
C2 > 1/ (2 ¥ 3.14 ¥ 30 ¥ R5)
R5
R4
R3
SG
Gain = 1 + R4 / R3 £ 10
AG
Analog signal ground.
AOUT
Analog output.
The output signal has a maximum amplitude of 2.0 V above and below the signal ground
PP
voltage (V /2).
DD
The output load resistance is a minimum of 1.2 kW.
During power saving or power down mode, the output of AOUT is at the voltage level of the
signal ground.
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OKI [ OKI ELECTRONIC COMPONETS ]
