Multimedia ICs
BA7760 / BA7760F
Measurement circuit
•
10kΩ
2.2kΩ
MIX BF
+
+
8
7
6
5
4
3
2
1
5kΩ
5kΩ
10µF
4.7µF
–
9
10
11
12
13
14
–
+
+
–
470µF
470µF
+
+
220Ω
220Ω
+
+
47µF
47µF
4.7µF
+
+
4.7µF
2.2kΩ
2.2kΩ
+
22µF
BA7760 / F
Fig. 2
Circuit operation (Refer to “Application Example”)
•
The BA7760 and BA7760F are dual microphone ampli-
fiers. The audio signals from the microphones are input
to pins 3 and 12. The gain at this time is determined by
attached resistors R3 / R4 and R6 / R7. By attaching
capacitors to pins 5 and 10, the microphone amplifiers
can be given frequency characteristics like those
shown below.
60dB
40dB
20dB
0dB
(Note: The attached component numbers are those used in “Application
Example.”)
180°
0°
– 20dB
3 61
3 61
3 61 3 61 3 61
– 180°
1kHz 10kHz 100kHz 1MHz 10MHz100MHz
FREQUENCY : f (Hz)
Characteristics when using standard
components and standard constants
Fig. 3 Microphone amplifier
frequency characteristics
4
ROHM [ ROHM ]
