HA12215F Datasheet, PDF (11/69 Pages) Hitachi Semiconductor – Audio Signal Processor for Cassette Deck(Dolby B-type NR with Recording System)

HA12215F
PB Equalizer
By switching logical input level of pin 17 (for Ain) and pin 19 (for Bin), you can equalize corresponding to
tape position at play back mode.
With the capacity C2 capacitance that we showed for figure 2 70 µs by the way figure seem to 3 they are
decided.
G_V
t1
t2
t1 = C2 ⋅ (12k + 15k)
t2 = C2 ⋅ 15k
f
Figure 3 Frequency Characteristic of PB Equalizer
The Sensitivity Adjustment of Music Sensor
Adjusting MS Amp gain by external resistor, the sensitivity of music sensor can set up.
REP
PB (L)
−6dB
V_CC
C16 _R13
1000p _330k
+ _C13
0.33µ
D V_CC
8.2k
LPF
25kHz
MAI
MA MSIN MS
R_L
100k
OUT
DET
−
+
MS AMP
DET
50k
MS OUT
GND
Microcomputer
GND
PB (R)
Figure 4 Music Sensor Block Diagram
Rev.5, Oct. 1999, page 11 of 69