CXA1897Q Datasheet, PDF (7/22 Pages) Sony Corporation – Dolby B Type Noise Reduction System with Recording/Playback Equalizer

CXA1897Q
Pin
No.
Symbol
DC
voltage
I/O
I/O
resistance
Equivalent circuit
Description
15 DECK AB — I
—
16 A EQ
20 SPEED
27 MODE
Vcc
15 ₁₄₇
16
20
27
GND
15 Playback input deck A/B
selector switch
Low : PB INA
Vcc
High : PB INB
16 Deck A equalizer selector
switch.
Low : 120µs EQ
High : 70µs EQ
20 R e c o r d i n g / p l a y b a c k
equalizer speed selector
switch.
Low : Normal speed
GND
High : High speed
(1.7 times normal speed)
27 Dolby NR mode selector
switch.
Low : Recording
(encoding)
High : Playback (decoding)
Vcc
Vcc
17 B EQ
2.5V I
(For
OPEN)
53kΩ
147 50k ^5k
17
5k
Deck B equalizer selector
switch.
Low : Normal tape, 120µs
EQ
Medium : CrO2 tape, 70µs EQ
High : Metal tape, 70µs
EQ
GND
GND
Vcc
Vcc
18 REC OUT1 4.0V O 147Ω
19 REC OUT2
×3
500
18
×2
19 ¹⁴⁷
500
×10
40k
5p
Recording equalizer output.
GND
GND
—7—