4.7Ω
I
TOT
+
10
820
33K
I
MIC
S1 V11 3.3k
0.022
8
22k
V1
1
220
7
3
10k
1kHz
0.01
S2
0.047
C2
2.2
R
G
*
C3
2.2
S3
2
10
4
+
4.7
2.2kΩ
23dB
40dB
0.047
1kΩ
5
MIC SUPPLY
6
9
S4
V
B
R
B
+
1.3 V DC
BATTERY
SIMULATOR
V
O
MICROPHONE SIMULATOR
NOTES:
1. 42.13 dB of attenuation from V1 to V11
2 *RG (equivalent gnd resistance) should not exceed 30 mΩ (increasing RG increases distortion)
All resistors in ohms, all capacitors in
µF
unless otherwise stated.
Fig. 1 Test Circuit
+ 4.7
NOTE1
+
6
0.022
8
23dB
0.047
3
4
0.01
+
2.2
10
40dB
0.047
1
2k TYP
10k
2.2
9
7
2
5
V
B
1.3 V DC
NOTE:
1. 2.2
µF
when receiver is
≥
3kΩ
All resistors in ohms, all capacitors in
µF
unless otherwise stated.
Fig. 2 Typical Hearing Aid Application
3
9
2.2k
6
1
2
27k
33k
8
5
10
7
4
All resistors in ohms, all capacitors in
µF
unless otherwise stated.
U.S. Patent No. 4,085,382, patented in other countries.
Fig.3 Functional Schematic
3
500 - 37 - 8
GENNUM [ GENNUM CORPORATION ]
