# LC75421

Manufacturer Part NumberLC75421
DescriptionElectronic Volume Controller for Cars
ManufacturerSanyo Semiconductor Corporation
LC75421 datasheet

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(4) Bass Peaking Circuit
The equivalent circuit and the formula for calculating the external RC with a mean frequency of 100 Hz are shown
below.
• Bass band equivalent circuit diagram
• Calculation example
Specification Mean frequency: f0 = 100 Hz
Gain during maximum boost: G = 11.9 dB
Let us use R1 = 0, R2 = 45.084 kΩ, and C1 = C2 = C.
We obtain R3 from G = 11.9 dB.
R2
G
20 LOG
1
+11.9 dB
10
2R3
R2
45084
R3
11.9dB/20
2 (3.936 – 1)
2 10
–1
We obtain C from mean frequency f0 = 100 Hz.
1
f 0
2
R3R2C1C2
1
1
C
2 f0 R3R2
2
100 45084 7680
We obtain Q.
R3R2
1
Q
1.66
2R3
R3R2
Simulation Results
Setting
f = 100 Hz
f = 1 kHz
11.9 dB
11.88
0.00
10.2 dB
10.38
0.00
8.5 dB
8.79
0.00
6.8 dB
7.14
0.00
5.1 dB
5.42
0.00
3.4 dB
3.66
0.00
1.7 dB
1.85
0.00
LC75421M
R1
R2
C1
C2
R3
7.68 K
0.082 F
No. 6866-20/24