ba3842f ROHM Co. Ltd., ba3842f Datasheet - Page 11

• Manufacturer Part Number: ba3842f
• Description: Preset Equalizer Sound Control P.s.c Ic
• Manufacturer: ROHM Co. Ltd.

(6)
(1) Low band
The low cutoff frequency fc of each mode is given by the
following equation :
fc = 1 / 2 CR = 1 / (2
When C = 0.22 F,
fc
The fc value can be changed to make slight changes in
the boost and cutoff gain of each mode.
(2) High band
The high cutoff frequencies fc of each mode are given by
the following equation :
fc = 1 / 2 CR
When C = 2200pF,
The fc values can be changed to make slight changes in
the boost and cutoff gain of each mode.
Note:
If a high or low fc value is changed, the gains of all modes
will change. The gain cannot be changed for only one
mode.
(7)
The band of ALC detection can be changed with the val-
ue of C
ic bass boost f
0.1 F, thus fc = 1 / 2 C
Audio ICs
160 (Hz)
ROCK : R = 8.0k
JAZZ : R = 10.7k
CLASSIC : R = 14.9k
BGM. POP : R = 17.4k
46 (Hz)
Filter for preset equalizer
ALC
4
. It must be adjusted appropriately for the dynam-
O
. In the example application circuit C
4
(R
C
5
/ / R
fc 9.0 (kHz)
fc 6.8 (kHz)
fc 4.8 (kHz)
fc 4.2 (kHz)
15.6k )
6
/ / R
7
)
4
=
The detection wave is dually rectified. In the example ap-
plication circuit, it is 1.3V
are connected as shown below, it will lower the ALC level.
Adjust the ALC level as needed. The detection band at
this time is :
fc = 1 / 2 C
(8)
Adjust the attack and release times with the resistors and
capacitors connected to the ALCC pin. The attack time
is determined by R
is determined by R
4.7 F, the ALC level may become unstable.
Attack time and release time
4
(R
5
/ / R
11
10
and C
(1k ) and C
6
/ / R
rms
5
. If the value set for C
, but if the resistors R
7
/ / R
8
5
/ / / R
, and the release time
9
)
BA3842F
5
8
is below
and R
573
9