BH3857 Rohm, BH3857 Datasheet - Page 12

• Manufacturer Part Number: BH3857
• Description: Audio sound controller
• Manufacturer: Rohm

(3)
The tone control provides gain boost or cut over a fre-
quency range that you decide. At the peak and bottom of
the frequency characteristic the boost is 15dB, and the
cut is *15dB (Typ.). Take the frequency characteristic
into consideration when designing the filter.
(1) Amount of tone boost
When the amount of volume attenuation is large, the tone
control width will change. Reference values are given be-
low.
Note, however, that the actual values will vary due to dif-
ferences in individual components.
Reference values :
S The bypass filter cutoff frequency (fc1) can be altered
S The bandwidth of the internal amplifier is determined
Audio ICs
by changing the value of the external capacitor C
by fc2 (about 100kHz).
Tone control width at 0dB volume attenuation :
Tone control width at *40dB volume attenuation :
Tone control width at *60dB volume attenuation :
15.0dB
13.5dB
12.0dB
Treble filter
The recommended value for fc1 is about 8kHz.
3
.
BH3857AFV
675