HA12209F Datasheet, PDF (12/49 Pages) Hitachi Semiconductor – Audio Signal Processor for Cassette Deck(Dolby B-type NR with Recording System)

HA12209F
Music Sensor Output (MSOUT)
As for internal circuit of music sensor block, music sensor out pin is connected to the collector of NPN type
directly, output level will be “high” when sensing no signal. And output level will be “low” when sensing
signal.
Connection with microcomputer, it is requested to use external pull up resistor (R_L = 10k to 22kΩ)
Note: Supply voltage of MSOUT pin must be less than V_CC voltage.
The Tolerances of External Components
For Dolby NR precision securing, please use external components shown at figure 7.
If leak-current are a few electrolytic-capacitor, it can be applicable to C2 and C15.
BIAS1
1
R1
33k
±2%
C15
0.1µ
±10%
39
DET (L)
HA12209
DET (R)
4
C2
0.1µ
±10%
Unit R : Ω
C:F
Figure 7 Tolerance of External Components
Low-Boost
EQIN
CEX2 REX1
CEX4
2.2µ 20k
0.47µ
Vin
REX2 REX3
6.8k 5.1k
+ _CEX3
0.47µ
GND
REC EQ
EQOUT
Unit R : Ω
C:F
Figure 8 Example of Low Boost Circuit
Rev.2, Jun. 1999, page 12 of 49