lc75410e Sanyo Semiconductor Corporation, lc75410e Datasheet - Page 20

• Manufacturer Part Number: lc75410e
• Description: Electronic Volume Controller For Car Audio Systems
• Manufacturer: Sanyo Semiconductor Corporation

F1/F2/F3 Band Circuit
The equivalent circuit and the formula for calculating the external RC with a mean frequency of 1 kHz are shown below.
• F1/F2/F3 band equivalent circuit block diagram
• Calculation example
Specification Mean frequency: f0 = 1 kHz
Gain during maximum boost: G
Let us use R1 = 0.027 kΩ, R2 = 38.861 kΩ and C1 = C2 = C.
1. Calculate R2 with G
2. Calculate C with the center frequency f0 = 1 kHz
3. Calculate Q:
G
R3 =
Q =
C
f =
+12 dB
0
=
2
2
(R1+R2)R3
10
f0
= 20 LOG
G/20
(R1+R2)R3C1C2
R2
(R1+R2)R3
1
1
–1
1
– R1
+12 dB
10
R3(R1+R2)
(2R3+R1)
= 12 dB:
=
1 +
+12 dB
2
2
2R3+R1
1000
R2
= 12 dB
C1
k
1
38888 6500
1.22
LC75410E, 75410W
R1
R3
R2
= 0.010 10
C2
–6
0.01 F
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