¡ 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
C1
Analog input
R1
GSX
AIN–
AIN+
SG
R1 : variable
R2 > 20 kW
C1 > 1/(2
¥
3.14
¥
30
¥
R1)
Gain = R2/R1
£
10
R2
–
+
2) Non inverting input type
C2
Analog input
R5
R4
R3
AIN+
AIN–
GSX
SG
+
–
R3 > 20 kW
R4 > 20 kW
R5 > 50 kW
C2 > 1/ (2
¥
3.14
¥
30
¥
R5)
Gain = 1 + R4 / R3
£
10
AG
Analog signal ground.
AOUT
Analog output.
The output signal has a maximum amplitude of 2.0 V
PP
above and below the signal ground
voltage (V
DD
/2).
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.
4/17
OKI [ OKI ELECTRONIC COMPONETS ]
