HA12207NT
Audio Signal Processor for Cassette Deck
ADE-207-197B (Z)
3rd Edition
Jun. 1999
Description
HA12207NT is silicon monolithic bipolar IC providing PB equalizer, REC equalizer system and each
electronic control switch in one chip.
Functions
• PB equalizer × 2 channel
• REC equalizer × 2 channel
• Each electronic control switch to change REC/PB etc.
• REC MUTE
• REC head return switch
Features
• REC equalizer is very small number of extern al parts, built-in 2 types of frequency characteristics.
• PB equalizer circuit built-in.
• REC /PB of high speed mode are possible with TYPE 1(Normal tape).
• Controllable from direct micro-computer output.
• Available to reduce substrate-area because of high integration and small external parts.
• As the pins arrangement resembles HA12185NT, it can design the board that is replaced with
HA12185NT.
HA12207NT
Pin Description, Equivalent Circuit (VCC = 10.5V, Vref = 5.6V, Ta = 25°C, No signal,
The value in the table show typical value.)
Pin No. Pin Name Note Equivalent Circuit Pin Description
1V
CC
V = V
CC
2 RECOUT (L) V = Vref
3RECOUT (R)
4 REC-RETURN V = Vref
V ’= Vref
V
CC
GND
I
VCC pin
REC-EQ output
V
REC return
CC
V4
5 pin, 6 pin
I
GND
V’
5 PB-IN B (L) PB B Deck input
6 PB-IN B (R)
7VREF V = Vref
V’ = V
/ 2
CC
8 PB-IN A (L) V = Vref
PB-IN
V
–+
10k
V'
10k
V
CC
V
Reference
V
CC
GND
PB A deck input
9 PB-IN A (R)
Rev.3, Jun. 1999, page 2 of 27
HA12207NT
Pin Description, Equivalent Circuit (VCC = 10.5V, Vref = 5.6V, Ta = 25°C, No signal,
The value in the table show typical value.)
Pin No. Pin Name Note Equivalent Circuit Pin Description
10 PB-NF (L) PB-IN = Vref
V
CC
PB-IN
PB EQ feed back
11 PB-NF (R)
12 PB-EQ (L) PBOUT = Vref
13 PB-EQ (R)
20 REC IN (R) V = Vref
21 REC IN (L)
14 PBOUT (R) V = Vref
180
330k
7
NAB output
PBOUT
GND
V
CC
100k
7Vref
V
CC
REC-EQ input
V
PB output
15 PBOUT (L)
GND
Rev.3, Jun. 1999, page 3 of 27
HA12207NT
Pin Description, Equivalent Circuit (VCC = 10.5V, Vref = 5.6V, Ta = 25°C, No signal,
The value in the table show typical value.)
Pin No. Pin Name Note Equivalent Circuit Pin Description
16 A/B I = 20µA
17 HSP
18 MUTE
19 IREF V = 1.9V
V
I
22k
100k
GND
V
Mode control input
CC
Equalizer
reference current
input
22 GND GND pin
Rev.3, Jun. 1999, page 4 of 27
Block Diagram
CC
GND
V
HA12207NT
C : F
Unit R : Ω
0.01µ 0.01µ
)
R
)(
L
(
(R)
(L)
/B
(R)
PB-EQPB-EQ
13 12
14
PB-OUT
PB-OUT
HSP
IREF
REC-IN
60µ
R-ch
12dB
120µ
L-ch
–
+
R-ch
AB
REC-EQ
11
)
R
PB-NFPB-NFPB-INPB-INPB-INPB-IN
10
)(
L
9
)(
R
(
A
)
L
(
A
VREF
470µ
+
)
R
(
B
)
L
(
B
REC-RETURN
(R)
REC-OUT
Bias
REC-IN
(L)
22 21 20 19 18 17 16 15
GND
L-ch
(L)
REC-OUT
CC
12345678
V
5.6k 5.6k
Rev.3, Jun. 1999, page 5 of 27
HA12207NT
Parallel Data Format
Pin No. Pin Name L H
17 HSP Normal * Hi speed
16 A/B Ain active * Bin active
Return SW ON * Return SW OFF
REC OUT active * REC OUT HIZ
18 MUTE MUTE ON * MUTE OFF
Note: Unforced pin state
Rev.3, Jun. 1999, page 6 of 27
HA12207NT
Functional Description
Power Supply Range
HA12207NT is designed to operate on single supply, shown by table 1.
Table 1 Supply Voltage
Item Power Supply Range
Single Supply 9.5V to 15.0V
Reference Voltage
As AC reference (Vref) of this IC has not a curr ent drivability, Vref fluctuates by A/B switching of PB-EQ.
Provided it causes you anxiety, please supply 7 pin with approximate 1/2 V
For example, a suitable circuit is shown by figure 1.
This IC has a capacitor charger for the Vref, indicated to the pin interface circuit figure.
voltage.
CC
470Ω
V
CC
1
22
GND
7
Vref
+
470µF
Figure 1 Reference Voltage Circuit
Lch PB-EQ Reference voltage
Lch REC-EQ Reference voltage
Rch REC-EQ Reference voltage
Rch PB-EQ Reference voltage
Rev.3, Jun. 1999, page 7 of 27
HA12207NT
Operating Mode Control
HA12207NT provides fully electronic switching circuits. And each operating mode control is controlled by
parallel data (DC voltage).
Table 2 shows the control voltage of each control input pin.
Table 2 Control Voltage (Vth)
Pin No. Lo Hi Unit Test Condition
16, 17 0.0 to 1.0 4.0 to V
CC
V
Input Pin Measure
V
18 0.0 to 3.0 4.0 to V
CC
V
Note: 1. Each pin is pulled down with 100kΩ internal resistor. 16 to 18 pins are low-level when each pin is
open.
2. Over shoot level and under shoot level of input signal must be the standardi ze d.
(High: Less than V
, Low: More than –0.2V)
CC
Block Diagram
Figure 2 shows the block diagram.
As this IC is built-in REC return switch, the configuration system can be simple system using a few
external component and the REC/PB head.
As this IC adopted Hi-z SW of REC-EQ output and the input mute system, it realizes REC mute
attenuation and pop-noise reduction securing in REC mute.
About these logics, please look at the Parallel Data Format.
REC IN
21
PBOUT
15
B head
A head
RECOUT
PB IN(B)
PB IN(A)
2
4
5
8
Hi-Z SW
RETURN SW
B
A
–
REC - EQ
+
+
–
Vref
Rev.3, Jun. 1999, page 8 of 27
7
10 13
Figure 2 Block Diagram (Lch)
Normal Speed
PB - A
HA12207NT
Level Block Diagram
The gain establishment of PB-EQ considers PB output level {(external AMP+PB AMP)=300mV(Dolby
Level)} like figure 3 as the target.
Regarding REC-EQ adjust the gain in front of input to this IC.
The level diagram of 1kHz is shown figure 4. (Normal speed)
Similarly to PB, it consider Dolby level as a standard. And R1 needs the value more than 5.6kΩ.
Because mode establishment resistances are built-in, REC-EQ frequ e n cy characteristics are respectiv ely
fixed value.
In case the change of the frequency characteristics are necessary, please inquire the responsible agent
because the adjustment of resistors is necessary.
300mV
(Dolby level)
63.6mV
HA12134A
0.6mV
40.5dB 20dB
PB-EQ
Dolby IC
Figure 3 PB Level Block Diagram (Normal Speed, 1kHz)
Rev.3, Jun. 1999, page 9 of 27
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