SONY CXA1878Q

CXA1878Q
Dolby∗ B-C Type Noise Reduction System with Recording/Playback Equalizer Amplifier
Description
The CXA1878Q is a bipolar IC with a built-in Dolby
B-C type noise reduction system (NR), Dolby S type
select switch, recording/playback equalizer, electronic
volume, and bias control circuit.
Use of this IC in combination with two CXA1417S/Q
completes a Dolby B-C-S type NR stereo system.
Features
• Dolby B-C type NR
• Built-in filter required for recording/playback equalizer
amplifiers
• Recording mute function
(requiring only an external time constant circuit to
implement soft mute)
• Fade in/out DC controllable
• NORM/CrO2/METAL tape mode switching function
• NORM/HIGH tape speed switching function
• DC controllable for recording level calibration
(approximately ±6dB variable)
• DC controllable for high frequency equalizer
amplifier gain (approximately ±4dB variable)
• Playback deck A/B select switch
• Recording volume control
• Bias control circuit
• Meter circuit
64 pin QFP (Plastic)
Structure
Bipolar silicon monolithic IC
Absolute Maximum Ratings
• Supply voltage
VCC
17
V
• Operating temperature
Topr –20 to +75 °C
• Storage temperature
Tstg –65 to +150 °C
• Allowable power dissipation PD
1020
mW
Operating Conditions
Supply voltage
(VCC • VEE) ±6.5 to 8.0
V
Applications
Recording/playback equalizer amplifier for stereo
analog cassette decks
(Applicable to ALPS ELECTRIC CO., LTD.
HADKH55 series heads)
∗ These ICs are available only to the licensees of Dolby Laboratories Licensing Corporation from whom licensing and applications
information may be obtained.
∗ “Dolby” and the double D symbols are trade marks of Dolby Laboratories Licensing Corporation.
Sony reserves the right to change products and specifications without prior notice. This information does not convey any license by
any implication or otherwise under any patents or other right. Application circuits shown, if any, are typical examples illustrating the
operation of the devices. Sony cannot assume responsibility for any problems arising out of the use of these circuits.
–1–
E95933A5Z-PK
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
NR RECIN1
VEE
LINE OUT1
METAL NORM CrO2
NR TCH1
REC-EQ
NR TCL1
VOL OUT1 64
NR OUT1
VOLUME
S IN1
CAL
B/C
S
REC IN1
METER1
METER2
VOLUME
CONT
33
NR RECOUT1
VOL IN1 63
PB
DOLBY
B-C NR
CXA1878Q
D GND
34
35
REC OUT1
GND
REC
ON METER
MUTE
GND
MUTE
S
B/C
CAL
36
37
DOLBY
B-C NR
AMS
38
IREF
GND
ON
CAL
OFF
ON
OFF CAL
ON METER
39
40
NR IREF
NR PBIN1 62
REC
MOA
CAL IN
41
MT C2
MT C1
PASS
MUTE
NR
CAL
REC MUTE
42
BS FB
BIAS M
OFF
ON
MOA
REC
PB
REC-EQ
REC OUT2
43
AMS FB
BIAS C
LINE
PB EQ
PB
PB
REC
NR RECOUT2
44
AMS TC
BIAS N
PB OUT1 61
B
DECK
S IN2
GND
45
AMS OUT
AMS SW
(OFF/AMS/BS)
PB INB1 60
A
ON
CAL
NR
MUTE
PASS
REC IN2
46
S SW
(S/BC/CAL)
PASS SW
(NR/MUTE/PASS)
PB INA1 59
GND
PB INA2 57
PB EQ
NR OUT2
47
REC CAL
METER SW
(ON/MUTE)
–2–
SPEED
(NS/HS)
GND 58
A
PB INB2 56
OFF
50
NR RECIN2
LINE
49
LINE OUT2
VOLUME
48
NR TCH2
DECK
B
PB OUT2 55
NR PBIN2 54
VOL IN2 53
VOL OUT2 52
NR TCL2
51
NR SW
(OFF/B/C)
Block Diagram and Pin Configuration
METER1
METER2
REC VOL
REC BAL
DGND
A EQ
(120µ/70µ)
MODE SW
20 (REC/PB)
21 VCC
22 DVCC
23
B EQ
24 (NORM/CrO2/METAL)
DECK A/B
25 (A/B)
26
27
28
29
30
31 VEE
32 GP CAL
CXA1878Q
CXA1878Q
Pin Description
Pin
No.
Symbol
(Ta = 25°C, VCC = 7.0V, VEE = –7.0V, DVCC = 5.0V)
Typical pin voltage
DC
AC
I/O
Z (in)
Equivalent circuit
Description
GND
40k
1
51
NR RECIN1
0.0V –26dBv
NR RECIN2
I
40kΩ
1.5k
Recording equalizer
amplifier input
1
51
300
2
50
LINE OUT1
LINE OUT2
0.0V –4dBv
O
—
3.4k
2
Line output
50
300
330k
3
49
NR TCH1
NR TCH2
VEE
+0.4V
13k
—
—
—
3
49
36k
Time constant for the
HLS
13.5k
4
48
NR TCL1
NR TCL2
VEE
+0.4V
—
—
—
Time constant for the
LLS
4
48
–3–
480k
CXA1878Q
Pin
No.
Symbol
5
47
NR OUT1
NR OUT2
Typical pin voltage
DC
AC
I/O
Z (in)
Equivalent circuit
192
–6dBm
0.0V
(–7dBv)
O
—
Description
12k
5
20k
47
192
Dolby S type NR output
1.5k
GND
6
46
S IN1
S IN2
0.0V
–6dBm
(–7dBv)
I
6
40kΩ
Dolby S type NR input
46
40k
GND
9.5k
7
45
REC IN1
REC IN2
0.0V –24dBv
I
50kΩ
Recording equalizer
amplifier input
7
45
50k
GND
211
8
44
NR RECOUT1
NR RECOUT2
–6dBm
0.0V
(–7dBv)
O
—
22.5k
8
44
211
1.5k
GND
–4–
Dolby NR recording
signal output
CXA1878Q
Typical pin voltage
Pin
No.
Symbol
9
43
REC OUT1
REC OUT2
DC
AC
I/O
Z (in)
Equivalent circuit
200
0.0V
–3dBv
O
—
Description
50k
Recording equalizer
amplifier output
9
43
200
Reference current
setting for built-in
recording/playback
equalizer amplifier
∗ The reference current
can be set by
connecting a resistor
between this pin and
VEE.
192
10
IREF
VEE
+1.2V
—
—
10
—
6k
8k
11
NR IREF
12
40
MT C1
MT C2
VEE
+1.2V
—
—
—
40k
Reference current
setting for built-in Dolby
NR
∗ The reference current
can be set by
connecting a resistor
between this pin and
VEE.
11
300
0.0V
—
O
—
14k
DC cut capacitance
12
40
–5–
300
CXA1878Q
Pin
No.
13
14
15
Symbol
BIAS M
BIAS C
BIAS N
Typical pin voltage
DC
AC
—
—
I/O
Z (in)
O
—
Equivalent circuit
Description
Recording bias control
voltage output
13
14
15
100k
16
AMS SW
2.5V
when
open
—
I
—
50k
5k
16
5k
24k
17
PASS SW
2.5V
when
open
—
I
—
50k
DGND
AMS mode control
∗ Mode select switch for
AMS/BS amplifier
High: BS mode
Medium: AMS mode
Low: AMS/BS OFF mode
[BS mode = Music
signal interval detection
during playback]
[AMS mode = Music
signal detection during
FF/REW]
PASS mode control
H : PASS
M : MUTE
L : NR ON
5k
17
5k
DGND
10k
18
METER SW
—
—
I
—
18
DGND
–6–
Meter mode control
∗ Meter amplifier output
ON/OFF select switch
High: Meter output
OFF (mute)
Low : Meter output ON
CXA1878Q
Pin
No.
Typical pin voltage
Symbol
DC
AC
I/O
Z (in)
Equivalent circuit
Description
Tape speed selection
∗ Normal speed/
double speed
selection
High: Double speed
Low : Normal speed
10k
19
SPEED
—
—
I
—
19
10k
DGND
2k
—
—
I
—
VCC
7.0V
—
I
—
Positive power supply
DVCC
5.0V
—
I
—
Reference power
supply for mode control
—
Deck A playback
equalizer amplifier
control
∗ 120µs/70µs selection
High: 70µs
Low : 120µs
(Built-in equalizer
amplifier flat)
20
MODE SW
21
22
23
Recording/playback
mode control
∗ Recording/playback
mode selection
High : Recording mode
Low : Playback mode
6k
A EQ
2.5V
when
open
—
I
20
23
10k
DGND
24
B EQ
2.5V
when
open
—
I
—
10k
24
DGND
–7–
Control of deck B
playback equalizer
amplifier mode,
recording equalizer
amplifier mode, and
recording bias mode
∗ NORM/CrO2/METAL
selection
High
: METAL
Medium : CrO2
Low
: NORM
CXA1878Q
Pin
No.
25
Typical pin voltage
Symbol
DECK A/B
DC
—
AC
—
I/O
I
Z (in)
Equivalent circuit
Description
10k
—
25
DGND
26
27
METER1
METER2
60k
1.6V –1.1dBv
O
—
26
Level meter amplifier
output
10k
27
Recording volume level
control
High: Output signal
level increased
Low : Output signal
level reduced
60k
28
REC VOL
—
—
I
100kΩ
Playback deck A/B
select control
∗ Playback equalizer
amplifier input
selection
High: PB INB
Low : PB INA
28
40k
GND
8k
29
REC BAL
2.5V
when
open
70k
—
I
100kΩ
29
30k
DVCC/2
30
DGND
8k
21k
Recording volume
balance control
High : Only VOL OUT2
output level
reduced
Low : Only VOL OUT1
output level
reduced
∗ Neither VOL OUT1
nor 2 output levels are
attenuated at the
control voltage of 2.5V.
Connect to GND.
0.0V
–8–
CXA1878Q
Pin
No.
31
32
33
34
Symbol
VEE
GP CAL
Typical pin voltage
DC
AC
I/O
Z (in)
Equivalent circuit
Description
–7.0V
Negative power supply
2.5V
when
open
Recording equalizer
amplifier high frequency
calibration
∗ Controlled with DC
voltages of 0 to 5V.
High: High frequency
level gain
increased
Low : High frequency
level gain
reduced
∗ Leave this pin open
when not using the
high frequency
calibration function.
REC CAL
2.5V
when
open
NR SW
2.5V
when
open
54k
—
I
54kΩ
32
Recording equalizer
amplifier calibration
∗ Controlled with DC
voltages of 0 to 5V.
High: Recording level
gain increased
Low : Recording level
gain reduced
∗ Leave this pin open
when not using the
recording calibration
function.
54k
—
I
54kΩ
33
2k
—
I
50kΩ
6k
34
50k
NR control
High: C type
Medium: B type
Low: NR OFF
DVCC/2
35
S SW
2.5V
when
open
2k
—
I
50kΩ
35
50k
DVCC/2
–9–
6k
Dolby S type selection
∗ Select the calibration
mode with this pin.
High: CALIBRATION
Medium: B-C type
Low: S type
CXA1878Q
Pin
No.
Symbol
36
AMS OUT
Typical pin voltage
DC
AC
0.0V
—
I/O
Z (in)
O
—
Equivalent circuit
Description
AMS amplifier output
36
10k
10k
DGND
10k
37
37
AMS TC
0.0V
—
—
—
1k
40k
Time constant for the
AMS
2p
38
AMS FB
0.0V
—
—
—
38
100k
Feedback during AMS
mode
2p
39
BS FB
0.0V
—
—
—
39
100k
– 10 –
Feedback during BS
mode
CXA1878Q
Pin
No.
Typical pin voltage
Symbol
DC
AC
I/O
Z (in)
Equivalent circuit
GND
1.5k
10k
41
CAL IN
0.0V –26dBv
I
10kΩ
Description
41
Calibration signal input
Recording mute
ON/OFF selection
∗ The recording mute is
controlled with DC
voltages of 0 to 5V.
30k
42
REC MUTE
—
—
I
—
42
GND
High: Recording mute OFF
Low : Recording mute ON
∗ Soft mute and fader
functions can be set by
changing the time
constant of the external
time constant circuit.
500
64
52
VOL OUT1
VOL OUT2
0.0V –10dBv
O
64
52
63
53
VOL IN1
VOL IN2
0.0V –10dBv
I
5p
50kΩ
63
53
– 11 –
500
6.5k
Recording volume
amplifier output
Recording volume
amplifier input
CXA1878Q
Pin
No.
Symbol
Typical pin voltage
DC
AC
I/O Z (in)
Equivalent circuit
Description
Dolby NR playback input
35.5k
62
54
NR PBIN1
NR PBIN2
0.0V –11dBv
I
40kΩ
2.9k
62
54
GND
61
55
PB OUT1
PB OUT2
0.0V –11dBv
I
—
4k
5k
500
8p
500
30k
61
55
GND
Playback equalizer
amplifier output
GND
59
59
60
57
56
PB INA1
PB INB1
PB INA2
PB INB2
0.0V –31dBv
58
GND
0.0V
60
I
50kΩ
57
56
—
—
—
50k
Playback equalizer
amplifier input
Ground
– 12 –
S1
S2
S3
S4
S5
R3
50k
Oscilloscope
Distortion
Analyzer
AC
Voltmeter
CCIR
1kHz BPF
DIN Audio
“A” WTG
GND GND
S6
R6
100
R7
100
R4
100
R5
100
VEE
S7
S8
S9
S10
C7
0.1µ
∗ R25
160k
∗ R8
2.7k
C1
0.1µ
–11dBv
C12
1.0µ
–31dBv
C13
0.1µ
–31dBv
GND
C14
0.1µ
–31dBv
–31dBv
C15
0.1µ
C16
0.1µ
∗ R20
10k
S11
1
VOL
OUT1
∗R30
5.1k
S21
C25
4.7µ
VOL IN1
PB OUT1
PB INB1
PB INA1
63
S19
C21
0.1µ
PB INA2
PB INB2
PB OUT2
NR PBIN2
2
C27
0.1µ
R32
2.7k
C29
0.068µ
5
4
3
C33
0.1µ
C31
2.2µ
∗ R34
32.1k
(1M//33k)
S23
6
C35
2.2µ
7
C37
4.7µ
S25
∗R36
5.1k
8
C39
2.2µ
R39
2.7k
S27
9
R41
2.7k
R42
27k
R45
27k
C43
1.0µ
11
10
R46
1k
I1
2mA
R48
1k
S38
S31
R50
1k
S31
S38
S31
14
13
12
R51
1k
S38
S31
15
R53
100k
16
17
18
26
25
24
23
22
21
METER1
DECK A/B
B EQ
A EQ
DVcc
Vcc
19
MODE
SW 20
27
28
29
30
31
32
METER2
REC VOL
REC BAL
DGND
VEE
GP CAL
33
34
35
36
37
38
39
40
41
42
R55
1k
43
S31
R54
100k
44
C47
0.1µ
45
R52
1MEG
46
C44
1.0µ
R49
10k
C46
0.015µ
47
VOL IN2
C23
2.2µ
C40
4.7µ
R47
1k
C45
1.5µ
48
NR PBIN1
64
C38
4.7µ
S28
S29
∗ R43
86k
(100k//
620k)
C42
2.2µ
S26
∗
R44
5.1k
49
C30
0.068µ
C41
0.1µ
∗
R40
2.7k
50
VOL
OUT2
GND
C28
0.1µ
∗
R37
5.1k
∗
R38
2.7k
51
62
61
60
59
58
57
56
55
54
53
52
∗ R28
86k
(100k//620k)
–10dBv
C9
1.0µ
C10 –10dBv
2.2µ
–11dBv
–11dBv
∗ R21
11.6k
C11
(12k//330k) 0.1µ
C2
0.1µ
∗R10 5.1k
∗R62 50k
∗ R9 5.1k
S12
S13
C3
0.1µ
∗ R22
∗ R12 5.1k 160k
∗ R11 2.7k
∗ R23
160k
S14
∗R24
160k
S15
∗ R13 5.1k
C4
0.1µ
–10dBv
C18
0.1µ
–10dBv
C19
2.2µ
C20
4.7µ
∗ R26
–11dBv
11.6k
C17
(12k//330k) 1.0µ
S16
∗R14 5.1k
C5
0.1µ
C6
0.1µ
∗R15 5.1k
∗ R16
2.7k
S17
∗ R17 5.1k
∗R18
5.1k
∗ R27
S18 10k
∗ R61 50k
C8
0.1µ
∗ R19
2.7k
NR RECIN1
–26dBv
Amp
0dB or 30dB
C26
4.7µ
LINE OUT1
–4dBv
C24
2.2µ
∗ R35
32.1k
(1M//33k)
C32
2.2µ
C36
2.2µ
–7dBv
∗ R29
86k
S24
C34
0.1µ
S IN1
–7dBv
S20
∗
R33
2.7k
REC IN1
–24dBv
DC
Voltmeter
S22
∗
R31
5.1k
–7dBv
C22
0.1µ
NR RECIN2
REC OUT1
–3dBv
GND
LINE OUT2
BIAS N
R2
1.2k
–26dBv
NR TCH2
AMS SW
R1
1.2k
–4dBv
NR TCL2
NR TCH1
NR OUT2
NR TCL1
S IN2
–7dBv
REC IN2
NR OUT1
NR RECOUT2
–7dBv
REC OUT2
PASS SW
Audio
SG
–24dBv
REC MUTE
–7dBv
CAL IN
NR RECOUT1
MT C2
METER SW
Amp
2.2dB
–3dBv
BS FB
–26dBv
AMS FB
IREF
AMS TC
NR IREF
AMS OUT
MT C1
S SW
BIAS M
NR SW
SPEED
– 13 –
BIAS C
REC
CAL
Electrical Characteristics Measurement Circuit
R62
1k
R63
1k
S39
S41
S53
S43
S45
R64
1k
S38
GND
GND
S44
C48
100µ
C49
100µ
S46
S47
S48
AMS MODE
AMS OFF
DOLBY NR
BS MODE
MUTE
METER ON
PASS
HIGH SPEED
NORMAL
SPEED
METER MUTE
PB
REC
PB A EQ FLAT
CrO2
NORMAL
PB A EQ 70µ
PB IN A
METAL
PB IN B
S55
S56
GND
GND
DOLBY B
DOLBY OFF
DOLBY C
DOLBY S
DOLBY B/C
C51
3.3µ
GND
S40
MUTE OFF
CALIBRATION
C52
3.3µ
GND
GND
L
M
H
MUTE ON
GND
S50
GND
S49
GND
S57
S58
S51
S52
S54
R65
1k
R66
1k
R67
1k
R68
1k
R59
R61 56k
1k
+1.1dBv
R60
56k
S32
S33
C50
10µ
S34
S35
S36
S37
+1.1dBv
R56
1k
R57
1k
R58
1k
V2
2.5
V1
0.5
V3
4.2
A
DC
Ammeter
5V
A
DC
Ammeter
A
GND
Power
Supply
DC
Ammeter
Vcc
VEE
CXA1878Q
GND
ERASE HEAD
REC/PB HEAD
[DECK-B]
REC/PB HEAD
[DECK-B (R)]
[DECK-B (L)]
GND
PB Only HEAD
[DECK-A (L)]
PB Only HEAD
[DECK-A (R)]
Bias
OSC
LINE IN
L-ch
R-ch
C8
150p
C2
75p
GND
C5
2.2µ
C6
2.2µ
C3
150p
R5
12k
C1
75p
L1
27mH
C4
2.2µ
GND
REC/PB
PB Amp
PB
REC
PB REC/PB
REC
PB Amp
PB Amp
PB Amp
R6
12k
L2
27mH
C7
2.2µ
R4
15k
R3
15k
GND
R10
100k
GND
C13
3.3µ
–3dBv
GND
–31dBv
–31dBv
–31dBv
–31dBv
C14
3.3µ
–3dBv
C10 R9
2.2µ 180k
C9
2.2µ –10dBv
–10dBv
R11
100k
GND
C15
2.2µ
C16
2.2µ
MPX
Filter
R13
3.3k
R42
50k
R41
50k
R14
3.3k
MPX
Filter
R15
8.2k
R17
2k
C17
2.2µ
3
4
DOLBY S NR
C21
0.068µ
R19
10k
7
6
5
8
C25
0.47µ
R21
4.7k
R22
8.2k
9
R25
27k
10
R26
20k
11
C30
1.0µ
12
BIAS
CONTROL
14
13
15
16
17
18
25
24
23
22
21
DECK A/B
B EQ
A EQ
DVCC
VCC
19
R31
56k
R32
56k
+1dBv
+1dBv
C35
3.3µ
26
METER1
MODE
SW 20
27
28
29
30
31
32
METER2
REC VOL
REC BAL
DGND
VEE
GP CAL
33
34
35
36
37
38
39
40
R30
100k
41
C34
0.1µ
42
R29
1MEG
C33
0.015µ
43
R28
10k
C32
1.5µ
44
R27
1k
C31
1.0µ
45
C26
2.2µ
CAL
OSC
C29
2.2µ
46
C23
2.2µ
C27
2.2µ
R23
8.2k
47
C19
0.1µ
C24
2.2µ
48
C22
0.068µ
C28
0.47µ
R24
4.7k
49
2
VOL
OUT1
C20
0.1µ
DOLBY S NR
R20
10k
50
1
VOL IN1
63
64
NR PBIN1
PB OUT1
PB INB1
PB INA1
GND
PB INA2
PB INB2
PB OUT2
NR PBIN2
VOL IN2
VOL
OUT2
51
C18
2.2µ
62
61
60
59
58
57
56
55
54
53
52
R16
8.2k
R18
2k
NR RECIN2
C11 R12
4.7µ 100k –6dBv
LINE OUT2
NR TCH1
GND R1
12k
NR TCH2
NR TCL1
–6dBv
NR TCL2
REC OUT1
L-ch
NR OUT2
IREF
LINE OUT
S IN2
NR IREF
–6dBv
REC IN2
MT C1
C12
4.7µ
NR RECOUT2
BIAS N
R-ch
REC OUT2
AMS SW
R7
4.7k
REC MUTE
PASS SW
R2
–6dBv 12k
CAL IN
METER SW
R8
4.7k
MT C2
NR RECIN1
BS FB
LINE OUT1
AMS FB
NR OUT1
AMS TC
S IN1
AMS OUT
REC IN1
S SW
NR RECOUT1
NR SW
BIAS M
REC
CAL
BIAS C
– 14 –
SPEED
C40
3.3µ
C36
1µ
C37
1µ
C38
10µ
C39
10µ
GND
C41
10µ
C42
10µ
R35
50k
GND
R33
50k
GND
R36
50k
GND
R34
50k
GP CAL
REC CAL
REC CALIBRATION
REC LEVEL & BALANSE
Application Circuit
R37
10k
R38
10k
HP Amp
HP Amp
REC MUTE
S SW
NR SW
DECK A/B
B-DECK EQ
A-DECK EQ
MODE (REC/PB)
SPEED
METER SW
PASS SW
AMS/BS
VCC
DVCC
METER (L)
METER (R)
to AMS Control
L : SIGNAL EXIST
H : NO SIGNAL
DVCC
VEE
HEADPHONES
R39
220
R40
220
CXA1878Q
to MICROCOMPUTER
7.3
2.9
7.1
11.3
3.9
NORM-tape, NORM-speed mode
Input a 3kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
NORM-tape, NORM-speed mode
Input a 8kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
NORM-tape, NORM-speed mode
Input a 12kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
CrO2-tape, NORM-speed mode
Input a 3kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
CrO2-tape, NORM-speed mode
Input a 8kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
CrO2-tape, NORM-speed mode
Input a 12kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
METAL-tape, NORM-speed mode
Input a 3kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
NORM-NORM mode
Recording
REC-EQ frequency response 1
equalizer amplifier
(3kHz, –20dB)
NORM-NORM mode
Recording
REC-EQ frequency response 2
equalizer amplifier
(8kHz, –20dB)
NORM-NORM mode
Recording
REC-EQ frequency response 3
equalizer amplifier
(12kHz, –20dB)
CrO2-NORM mode
Recording
REC-EQ frequency response 1
equalizer amplifier
(3kHz, –20dB)
CrO2-NORM mode
Recording
REC-EQ frequency response 2
equalizer amplifier
(8kHz, –20dB)
CrO2-NORM mode
Recording
REC-EQ frequency response 3
equalizer amplifier
(12kHz, –20dB)
METAL-NORM mode
Recording
REC-EQ frequency response 1
equalizer amplifier
(3kHz, –20dB)
2.5
–1.9
–26
Input level when the reference output level is 315Hz, –3.0dBv
(For measurement, input a 315Hz, –24.5dBv signal to the REC EQ IN
pins (Pins 7 and 45) and then measure the output level.)
Recording equalizer amplifier
Recording
Recording reference input level
equalizer amplifier
NORM-NORM mode
—
Recording equalizer amplifier reference output level (315Hz)
(This output level is the tape reference 0dB which generates magnetic
flux of 250nWb/m)
All of the recording equalizer amplifier blocks use this level as their
reference level.
Recording equalizer amplifier
Recording
Recording reference output
equalizer amplifier level
NORM-NORM mode
±6.5
Operating voltage range
(positive/negative dual power
supplies)
Entire LSI
Min.
28
Conditions
Current consumption (ICC)
Item
– 15 –
5.4
14.3
9.1
4.4
10.3
4.5
–0.4
–24.5
–3.0
±7.0
38
Typ.
6.9
17.3
11.1
5.9
13.3
6.5
1.0
–23
—
±8.0
48
Max.
dB
dB
dB
dB
dB
dB
dB
dBv
dBv
V
mA
Unit
(Ta = 25°C, VCC = 7.0V, VEE = –7.0V)
Entire LSI
Block
Electrical Characteristics
CXA1878Q
CrO2-tape, HIGH-speed mode
Input a 15kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
CrO2-tape, HIGH-speed mode
Input a 20kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
METAL-tape, HIGH-speed mode
Input a 5kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
METAL-tape, HIGH-speed mode
Input a 15kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
METAL-tape, HIGH-speed mode
Input a 20kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
CrO2-HIGH mode
Recording
REC-EQ frequency response 3
equalizer amplifier
(20kHz, –20dB)
METAL-HIGH mode
Recording
REC-EQ frequency response 1
equalizer amplifier
(5kHz, –20dB)
METAL-HIGH mode
Recording
REC-EQ frequency response 2
equalizer amplifier
(15kHz, –20dB)
METAL-HIGH mode
Recording
REC-EQ frequency response 3
equalizer amplifier
(20kHz, –20dB)
NORM-tape, HIGH-speed mode
Input a 20kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
NORM-HIGH mode
Recording
REC-EQ frequency response 3
equalizer amplifier
(20kHz, –20dB)
CrO2-HIGH mode
Recording
REC-EQ frequency response 2
equalizer amplifier
(15kHz, –20dB)
NORM-tape, HIGH-speed mode
Input a 15kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
NORM-HIGH mode
Recording
REC-EQ frequency response 2
equalizer amplifier
(15kHz, –20dB)
CrO2-tape, HIGH-speed mode
Input a 5kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
NORM-tape, HIGH-speed mode
Input a 5kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
NORM-HIGH mode
Recording
REC-EQ frequency response 1
equalizer amplifier
(5kHz, –20dB)
CrO2-HIGH mode
Recording
REC-EQ frequency response 1
equalizer amplifier
(5kHz, –20dB)
METAL-tape, NORM-speed mode
Input a 12kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
METAL-NORM mode
Recording
REC-EQ frequency response 3
equalizer amplifier
(12kHz, –20dB)
Conditions
METAL-tape, NORM-speed mode
Input a 8kHz signal (–20dB level down) to the REC EQ IN pin and
then measure the relative deviation from NORM-NS, 315Hz mode.
Item
METAL-NORM mode
Recording
REC-EQ frequency response 2
equalizer amplifier
(8kHz, –20dB)
Block
– 16 –
11.8
9.5
5.9
11.4
8.6
3.9
7.4
4.0
–1.3
10.4
7.1
Min.
15.3
12.0
7.4
14.9
11.1
5.4
10.9
6.5
0.2
13.4
9.1
Typ.
18.8
14.5
8.9
18.4
13.6
6.9
14.4
9.0
1.7
16.4
11.1
Max.
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
Unit
CXA1878Q
Item
NORM-tape, NORM-speed mode, RL = 2.7kΩ
Input a 1kHz signal and set the output level so that THD (total harmonic
distortion) is 1%. (Measure the distortion of a +11dB level-up signal.)
Conditions
NORM-tape, NORM-speed mode
With no signal, measure the DC offset voltage of the REC OUT pin.
NORM-NORM mode
Recording
Output DC offset voltage
equalizer amplifier
(REC OUT pin)
– 17 –
–7.5
2.7
–4.8
8.0
NORM-tape, NORM-speed mode, REC-CAL = 0.0V
NORM-NORM mode
Recording
REC-EQ REC-CAL characteristics 2 Input a 315Hz signal (–20dB level down) and measure the amount of change
equalizer amplifier
compared to when the REC-CAL function is at the standard setting.
(REC-CAL = 0.0V)
NORM-tape, NORM-speed mode, Gp-CAL = 5.0V
NORM-NORM mode
Recording
REC-EQ Gp-CAL characteristics 1 Input a 8kHz signal (–20dB level down) and measure the amount of change
equalizer amplifier
compared to when the Gp-CAL function is at the standard setting.
(Gp-CAL = 5.0V)
NORM-tape, NORM-speed mode, Gp-CAL = 0.0V
NORM-NORM mode
Recording
REC-EQ Gp-CAL characteristics 2 Input a 8kHz signal (–20dB level down) and measure the amount of change
equalizer amplifier
compared to when the Gp-CAL function is at the standard setting.
(Gp-CAL = 0.0V)
REC-VOL = 5.0V, REC-BAL = 2.5V
Recording volume amplifier
Recording volume Recording volume characteristics 1 Input a 1kHz, –10dBv signal to the VOL IN pin and measure the full
(REC-VOL = 5.0V, REC-BAL = 2.5V) gain of the recording volume amplifier.
9.0
–3.3
4.2
–6.0
6.3
4.8
NORM-tape, NORM-speed mode, REC-CAL = 5.0V
NORM-NORM mode
Recording
REC-EQ REC-CAL characteristics 1 Input a 315Hz signal (–20dB level down) and measure the amount of change
equalizer amplifier
compared to when the REC-CAL function is at the standard setting.
(REC-CAL = 5.0V)
–99.9
10.0
65.0
0.14
12.4
Typ.
–6.6
—
–500
57.0
—
11.0
Min.
NORM-tape, NORM-speed mode, REC-MUTE = 2.5V
NORM-NORM mode
Recording
REC-EQ mute characteristics 2 Input a 1kHz, 0dB (reference level) signal and measure the attenuation –8.1
equalizer amplifier
characteristics curve of the soft mute function (when REC-MUTE = 2.5V).
(REC-MUTE = 2.5V)
NORM-tape, NORM-speed mode, REC-MUTE = 0.5V
NORM-NORM mode
Recording
REC-EQ mute characteristics 1 Input a 1kHz signal (+12dB level up) and measure the attenuation
equalizer amplifier
when REC MUTE is ON. (Use a 1kHz BPF.)
(REC-MUTE = 0.5V)
NORM-tape, NORM-speed mode, Rg = 5.1kΩ
With no signal, measure the noise using the “A”-WGT filter. (The measured
value is indicated as the relative value compared to the reference level.)
NORM-NORM mode
Recording
REC-EQ S/N ratio
equalizer amplifier
(“A”-WGT filter)
NORM-tape, NORM-speed mode, RL = 2.7kΩ
NORM-NORM mode
Recording
REC-EQ total harmonic distortion Input a 1kHz, 0dB (reference input level) signal and measure the distortion.
equalizer amplifier
(Measure the distortion as THD + N.)
(1kHz, 0.0dB, RL = 2.7kΩ)
NORM-NORM mode
Recording
REC-EQ signal handling
equalizer amplifier
(1kHz, THD = 1%, RL = 2.7kΩ)
Block
10.0
–1.8
5.7
–4.5
7.8
–5.1
–80
500
—
0.6
—
Max.
dB
dB
dB
dB
dB
dB
dB
mV
dB
%
dB
Unit
CXA1878Q
– 18 –
—
6.0
6.0
12.0
REC-VOL = 5.0V, REC-BAL = 5.0V, (1kHz BPF)
Recording volume amplifier
Recording volume REC-VOL balance characteristics 2 Input a 1kHz, +2dBv signal and measure the attenuation of VOL OUT 2.
(REC-VOL = 5.0V, REC-BAL = 5.0V) (Input a –10dBv signal and confirm that there is no attenuation at VOL OUT 1.)
Line amplifier
NR mode
NR mode gain
Input a 1kHz, –11dBv signal to the NR PB IN pin and measure the gain.
(NR PB IN = 1kHz, –11.0dBv)
Line amplifier
PASS mode
PASS mode gain
Input a 1kHz, –11dBv signal to the NR PB IN pin and measure the gain.
(NR PB IN = 1kHz, –11.0dBv)
PASS mode, RL = 2.7kΩ
Line amplifier
Input a 1kHz signal and set the output level so that the THD is 1%.
Signal handling
(1kHz, THD = 1%, RL = 2.7kΩ) (Measure the distortion when the output is +1dBv.)
Line amplifier
Line amplifier
Line amplifier
–150
—
REC-VOL = 5.0V, REC-BAL = 2.5V
With no signal, measure the DC offset voltage of the VOL OUT pin.
REC-VOL = 5.0V, REC-BAL = 0.0V, (1kHz BPF)
Recording volume amplifier
Recording volume REC-VOL balance characteristics 1 Input a 1kHz, +2dBv signal and measure the attenuation of VOL OUT 1.
(REC-VOL = 5.0V, REC-BAL = 0.0V) (Input a –10dBv signal and confirm that there is no attenuation at VOL OUT 2.)
Recording volume amplifier
Recording volume Output DC offset voltage
(VOL OUT pin)
80
—
REC-VOL = 2.0V, REC-BAL = 2.5V, RL = 2.7kΩ
Recording volume amplifier
Recording volume REC-VOL total harmonic distortion Input a 1kHz, –10dBv signal (reference input level) and measure the
distortion. (Measure the distortion as THD + N.)
(1kHz, –6.0dBv, RL = 2.7kΩ)
REC-VOL = 5.0V, REC-BAL = 2.5V
With no signal, measure the noise using an “A”-WGT filter. (The measured
value is indicated as the relative value compared to the full-gain level.)
2.0
REC-VOL = 2.0V, REC-BAL = 2.5V, RL = 2.7kΩ
Recording volume amplifier
Input a 1kHz signal and set the input level so that the THD is 1%.
Recording volume REC-VOL signal handling
(1kHz, THD = 1%, RL = 2.7kΩ) (Measure the distortion when the output is +2dBv.)
Recording volume amplifier
Recording volume REC-VOL S/N ratio
(“A”-WGT filter)
—
Min.
REC-VOL = 0.0V, REC-BAL = 2.5V
Recording volume amplifier
Recording volume Recording volume attenuation Input a 1kHz, +2dBv signal and measure the maximum volume
(REC-VOL = 0.0V, REC-BAL = 2.5V) attenuation of the recording volume amplifier. (Use a 1kHz BPF.)
Conditions
–9.4
Item
REC-VOL = 2.0V, REC-BAL = 2.5V
Recording volume amplifier
Recording volume Recording volume characteristics 2 Input a 1kHz, –10dBv signal to the VOL IN pin and measure the
(REC-VOL = 2.0V, REC-BAL = 2.5V) attenuation of the recording volume amplifier.
Block
15.5
7.0
7.0
–93.2
–93.2
4.2
97.5
0.09
3.41
–104.7
–8.4
Typ.
—
8.0
8.0
–60
–60
150
—
0.5
—
–80
–7.4
Max.
dB
dB
dB
dB
dB
mV
dB
%
dBv
dB
dB
Unit
CXA1878Q
Conditions
—
1.34
MUTE mode
Input a 1kHz, +1dBv signal to the NR PB IN pin and measure the
attenuation when LINE MUTE is on. (Use a 1kHz BPF.)
METER ON, CAL OFF, PB
Input a 1kHz, –11dBv signal to the NR PB IN pin and measure the
output DC voltage at the METER pin.
Line amplifier
MUTE mode characteristics
(1kHz BPF)
Level meter amplifier
Level meter characteristics 1
(PASS IN = 1kHz, –11dBv)
Line amplifier
Level meter
– 19 –
—
METER MUTE ON, PB
Level meter amplifier
Level meter MUTE characteristics Input a 1kHz, +1dBv (12dB level up) signal to the NR PB IN pin and
measure the output DC voltage at the METER pin.
(PASS IN = 1kHz, +1.0dBv)
Level meter
3.0
1.6
0.5
1.64
–111
0
84.1
0.07
Typ.
–1.0
–5.7
DECK-A, A-EQ = 120µs, NORM-speed mode
Input a 5kHz, –31dBv (reference input level) signal and then measure
the relative deviation from the 120µs-NS, 315Hz mode.
DECK-A, A-EQ = 70µs, NORM-speed mode
Input a 5kHz, –31dBv (reference input level) signal and then measure
the relative deviation from the 120µs-NS, 315Hz mode.
Playback equalizer amplifier
Playback
PB-EQ frequency response 1
equalizer amplifier
120µs-NS, DECK-A mode
Playback equalizer amplifier
Playback
PB-EQ frequency response 2
equalizer amplifier
70µs-NS, DECK-A mode
–4.2
0.0
–11.9 –10.9
1.3
METER ON, CAL ON, REC
Level meter amplifier
Level meter CAL characteristics Input a 1kHz, –28dBv (–17dB level down) signal to the NR PB IN pin
and measure the output DC voltage at the METER pin.
(PASS IN = 1kHz, –28dBv)
Level meter
DECK-A, A-EQ = 120µs, NORM-speed mode
120µs, DECK-A mode
Playback
Playback reference output level Input a 315Hz, –31dBv (reference input level) signal to the PB IN pin
equalizer amplifier
(Playback equalizer amplifier gain) and measure the output level.
0.2
METER ON, CAL OFF, PB
Input a 1kHz, –21dBv (–10dB level down) signal to the NR PB IN pin
and measure the output DC voltage at the METER pin.
Level meter amplifier
Level meter characteristics 2
(PASS IN = 1kHz, –21dBv)
Level meter
–200
PASS mode
With no signal, measure the DC offset voltage of the LINE OUT pin.
Line amplifier
Output DC offset voltage
(LINE OUT pin)
Line amplifier
80
PASS mode, Rg = 5.1kΩ
With no signal, measure the noise using the “A”-WGT filter. (The measured
value is indicated as the relative value compared to the reference level.
—
Min.
Line amplifier
Line amplifier S/N ratio
(“A”-WGT filter)
PASS mode, RL = 2.7kΩ
Line amplifier
Line amplifier total harmonic distortion Input a 1kHz, –11dBv signal (reference input level) and measure the
(1kHz, –11.0dBv, RL = 2.7kΩ) distortion. (Measure the distortion as THD + N.)
Item
Line amplifier
Line amplifier
Block
–2.7
1.0
–9.9
50.0
1.9
0.8
1.94
–80
200
—
1.0
Max.
dB
dB
dBv
mV
V
V
V
dB
mV
dB
%
Unit
CXA1878Q
– 20 –
1.0
AMS/BS amplifier
0.88
AMS OFF mode
Input a 5kHz, –11dBv signal to the NR PB IN pin and measure the
current flowing to the AMS OUT pin.
AMS/BS amplifier
AMS output leak current
(AMS OUT pin)
AMS/BS amplifier
—
–35.5 –30.5 –25.5
BS mode, fin = 5kHz, reference level –11dBv
Input level when the AMS OUT pin level changes from high to low.
Input the signal to the NR PB IN pin and measure the level at the AMS
OUT pin.
AMS/BS amplifier
BS signal detection level
BS mode
–5.0
–15.0 –10.0
1.0
AMS/BS amplifier
0.0
200
—
0.5
—
–7.1
–3.8
Max.
AMS mode, fin = 5kHz, reference level –11dBv
Input level when the AMS OUT pin level changes from high to low.
Input the signal to the NR PB IN pin and measure the level at the AMS
OUT pin.
–1.0
DECK-B, B-EQ = NORM-tape, NORM-speed mode
Input a 1kHz, –31dBv (reference input level) signal to the DECK-B
side and then measure the relative deviation from the DECK-A, 120µs-NS,
315Hz mode.
Recording equalizer amplifier
DECK-A/B switching
Playback
equalizer amplifier characteristics
120µs-NS, DECK-B mode
–5
75.6
0.03
22
–8.6
–5.3
Typ.
AMS/BS amplifier
AMS signal detection level
AMS mode
–200
70
DECK-A, A-EQ = 120µs, NORM-speed mode
With no signal, measure the DC offset voltage of the PB OUT pin.
DECK-A, A-EQ = 120µs, NORM-speed mode, Rg = 5.1kΩ
With no signal, measure the noise using the “A”-WGT filter. (The measured
value is indicated as the relative value compared to the reference level.)
120µs-NS, DECK-A mode
Playback
Output DC offset voltage
equalizer amplifier
(PB OUT pin)
120µs-NS, DECK-A mode
Playback
PB-EQ S/N ratio
equalizer amplifier
(“A”-WGT filter)
—
DECK-A, A-EQ = 120µs, NORM-speed mode, RL = 2.7kΩ
120µs-NS, DECK-A mode
Playback
PB-EQ total harmonic distortion Input a 1kHz, –31dBv (reference input level) signal and measure the
equalizer amplifier
distortion. (Measure the distortion as THD + N.)
(1kHz, 0.0dB, RL = 2.7kΩ)
–10.1
DECK-A, A-EQ = 70µs, HIGH-speed mode
Input a 5kHz, –31dBv (reference input level) signal and then measure
the relative deviation from the 120µs-NS, 315Hz mode.
Playback equalizer amplifier
Playback
PB-EQ frequency response 4
equalizer amplifier
70µs-HS, DECK-A mode
12
–6.8
DECK-A, A-EQ = 120µs, HIGH-speed mode
Input a 5kHz, –31dBv (reference input level) signal and then measure
the relative deviation from the 120µs-NS, 315Hz mode.
Playback equalizer amplifier
Playback
PB-EQ frequency response 3
equalizer amplifier
120µs-HS, DECK-A mode
DECK-A, A-EQ = 120µs, NORM-speed mode, RL = 2.7kΩ
120µs-NS, DECK-A mode
Playback
Input a 1kHz signal and set the output level so that the THD is 1%.
PB-EQ signal handling
equalizer amplifier
(1kHz, THD = 1%, RL = 2.7kΩ) (Measure the distortion of a +12dB level-up signal.)
Min.
Item
Conditions
Block
µA
dB
dB
dB
mV
dB
%
dB
dB
dB
Unit
CXA1878Q
Min.
–11
1.4
3.9
9.7
–1.1
PB mode, NR OFF, f = 1kHz
Input a signal to the NR PB IN pin and measure the level at which the
level of the DOLBY OUT pin reaches –6dBm.
REC, Dolby B type mode
Input a 500Hz, –25dB signal from the REC IN pin and measure the
boost at the REC OUT pin.
REC, Dolby B type mode
Input a 5kHz, –25dB signal from the REC IN pin and measure the
boost at the REC OUT pin.
REC, Dolby B type mode
Input a 10kHz, –40dB signal from the REC IN pin and measure the
boost at the REC OUT pin.
REC, Dolby B type mode
Input a 10kHz, 0dB signal from the REC IN pin and measure the
boost at the REC OUT pin.
PB mode
PB IN level
B type encoding
Boost characteristics 1
B type encoding
Boost characteristics 2
B type encoding
Boost characteristics 3
B type encoding
Boost characteristics 4
DOLBY
DOLBY
DOLBY
DOLBY
DOLBY
–26
REC mode, NR OFF, f = 1kHz
Input a signal to the REC IN pin and measure the level at which the
level of the DOLBY OUT pin reaches –6dBm.
REC mode
REC IN level
DOLBY
–26
—
REC mode, NR OFF
1kHz, assume Dolby level of –6dBm as 0dB.
Dolby level
DOLBY
REC mode, NR OFF, f = 1kHz
Input a signal to the CAL IN pin and measure the level at which the
level of the DOLBY OUT pin reaches –6dBm.
—
Input a 2mA signal to the BIAS M pin and measure the DC output
voltage at the BIAS M pin.
BIAS M output voltage
(METAL mode)
BIAS SW
REC mode
CAL IN level
—
Input a 2mA signal to the BIAS C pin and measure the DC output
voltage at the BIAS C pin.
BIAS C output voltage
(CrO2 mode)
BIAS SW
DOLBY
—
Input a 2mA signal to the BIAS N pin and measure the DC output
voltage at the BIAS N pin.
BIAS N output voltage
(NORMAL mode)
—
Conditions
AMS mode
AMS/BS amplifier
AMS output saturation voltage Input a 5kHz, –11dBv signal to the NR PB IN pin and measure the
output voltage when a 1mA current flows to the AMS OUT pin.
(AMS OUT pin)
Item
BIAS SW
AMS/BS amplifier
Block
– 21 –
0.4
10.4
5.4
2.9
–10
–25
–25
–6.0
0.4
0.4
0.4
0.17
Typ.
1.9
11.4
6.9
4.4
–9
–24
–24
—
0.6
0.6
0.6
1.0
Max.
dB
dB
dB
dB
dBm
dBm
dBm
dBm
V
V
V
V
Unit
CXA1878Q
–1.5
13.5
—
—
—
PB, Dolby C type mode
Input a 20kHz, –10dBm signal from the NR PB IN pin and measure
the relative deviation from the REC OUT output NR OFF mode.
REC, NR OFF mode
Input a 1kHz signal and set the output level so that the THD is 1%.
(Measure the distortion using a +13.5dB level-up signal from the reference.)
REC, NR OFF mode
Input a 1kHz, +10dB signal from the REC IN pin and measure the
distortion. (Measure the distortion as THD + N.)
REC, Dolby B type mode
Input a 1kHz, +10dB signal from the REC IN pin and measure the
distortion. (Measure the distortion as THD + N.)
REC, Dolby C type mode
Input a 1kHz, +10dB signal from the REC IN pin and measure the
distortion. (Measure the distortion as THD + N.)
PB mode
Frequency response
REC mode
Signal handling
NR OFF total harmonic
distortion
Dolby B type total harmonic
distortion
Dolby C type total harmonic
distortion
DOLBY
DOLBY
DOLBY
DOLBY
DOLBY
3.5
REC, Dolby C type mode
Input a 5kHz, –25dB signal from the REC IN pin and measure the
boost at the REC OUT pin.
C type encoding
Boost characteristics 5
DOLBY
–5.5
5.4
REC, Dolby C type mode
Input a 2kHz, –25dB signal from the REC IN pin and measure the
boost at the REC OUT pin.
C type encoding
Boost characteristics 4
DOLBY
REC, Dolby C type mode
Input a 10kHz, 0dB signal from the REC IN pin and measure the
boost at the REC OUT pin.
18.7
REC, Dolby C type mode
Input a 2kHz, –60dB signal from the REC IN pin and measure the
boost at the REC OUT pin.
C type encoding
Boost characteristics 3
DOLBY
C type encoding
Boost characteristics 6
7.2
REC, Dolby C type mode
Input a 500Hz, –25dB signal from the REC IN pin and measure the
boost at the REC OUT pin.
C type encoding
Boost characteristics 2
DOLBY
DOLBY
14.2
Min.
REC, Dolby C type mode
Input a 500Hz, –60dB signal from the REC IN pin and measure the
boost at the REC OUT pin.
Conditions
C type encoding
Boost characteristics 1
Item
DOLBY
Block
– 22 –
0.09
0.06
0.04
15.4
0
–3.5
5.5
7.4
20.7
9.2
16.2
Typ.
0.5
0.5
0.5
—
1.5
–1.5
7.5
9.4
22.7
11.2
18.2
Max.
%
%
%
dB
dB
dB
dB
dB
dB
dB
dB
Unit
CXA1878Q
– 23 –
Control circuit
Control circuit
Control circuit
Control circuit
0.0
NR SW, S SW, DECK A/B, EQ, B EQ, and PASS SW pin voltages
AMS SW, MODE SW, SPEED, and METER SW pin voltages
AMS SW, MODE SW, SPEED, and METER SW pin voltages
Mode control
Control circuit low level
Mode control
Control circuit high level
Mode control
Control circuit low level
0.0
3.5
2.2
Mode control
NR SW, S SW, DECK A/B, EQ, B EQ, and PASS SW pin voltages
Control circuit medium level
4.2
REC mode, NR OFF → C type
With no signal, measure the deviation in the output DC offset voltage at –100
the REC OUT pin when switching from NR OFF mode to C type mode.
REC mode
Output DC offset voltage
(REC OUT pin)
DOLBY
NR SW, S SW, DECK A/B, EQ, B EQ, and PASS SW pin voltages
—
REC, NR OFF mode
Input a 1kHz, +10dB signal from the NR PB IN pin and measure the
PB → REC crosstalk. (Use a 1kHz BPF.)
REC mode
Playback → recording
crosstalk
DOLBY
Mode control
Control circuit high level
—
PB, NR OFF mode
Input a 1kHz, +10dB signal from the REC IN pin and measure the
REC → PB crosstalk. (Use a 1kHz BPF.)
PB mode
Recording → playback
crosstalk
DOLBY
Control circuit
60.0
Min.
Conditions
DOLBY
Item
REC, Dolby C type mode, Rg = 5.1kΩ
With no signal, measure the noise using the CCIR/ARM filter.
(The measured value is indicated as the relative value compared to the
DOLBY OUT level.)
Binary swithing Ternary switching
REC mode
Dolby C type S/N ratio
Block
—
—
—
—
—
0.0
–113
–77.5
61.0
Typ.
0.5
VCC
0.5
2.8
VCC
100
–70
–70
—
Max.
V
V
V
V
V
mV
dB
dB
dB
Unit
CXA1878Q
GND
10k
to Control IC
GND
R1
50k
DVcc
for R-ch
R-ch
GND
[DECK-A]
VEE
GND
C2
2.2µ
R5 20k
R6 27k
2.2µ
PB Amp C1
PB Only HEAD
– 24 –
DVCC
VEE
GND
VEE
Vcc
R2
50k
C3
R7
2.2µ
50k
R3
GND
180k
GND
GND
R4
15k
∗ Sourse Impedance 10kΩ
L-ch
LINE IN
–6dBv
600
–11dBv
R11
18k
PRE
VGS
(C)
R10
2k
D1
B DECK
VGS
(C)
–31dBv
R8
50k
PB INB
–31dBv
PB INA A DECK
R9
50k
VGS
(C)
NR IREF
DGND
DVcc
IREF (REC/PB)
GND (VG)
VEE
Vcc
S SW (S/BC/CAL)
AMS SW
(OFF/AMS/BS)
NR SW (OFF/B/C)
MODE SW (REC/PB)
METER SW (ON/MUTE)
REC BAL
PASS SW
(NR/MUTE/PASS)
REC VOL
REC MUTE
DECK A/B (A/B)
R12
6.5k
–10dBv
×1
SPEED (NS/HS)
B EQ (N/C/M)
A EQ (120/70)
–10dBv
VOL IN
to LINE IN
Gmb
C4
200p
–11dBv
BIAS
GND
(A)
PEA
R14
30k
RVA
R13
6.5k
CONTROL
VGS VGS
(C) (B)
Gm1
R15
3.3k
–14dBv
R17
40k
R18
6.2k
C5
2.2µ
PB OUT
–11dBv
(–30dBm)
–31dBv
R16
36k
NRPB IN
(–10dBm)
–11dBv
×1
R26
12k
R24
22.5k
VGS
(C)
R25
1.5k
R29
100k
VEE
–26dBv
BS FB
GND
C11
1.5µ
C9
0.015µ
GND
R33
1k
BS
–15dBv
R30
10k
AMS FB
AMS/BS
AMS
PASS
COMP
METER
OFF
R46
2k
R47
12k
R44
3.3k
for R-ch
R-ch
R50
4.7k
C16
4.7µ
–4dBv
GND
(A)
HP Amp
R55
220
×1
Gm5
GND
for R-ch
DGND
REA
B EQ
MTR
C21
3.3µ
METER
GND
R67
50k
GND
47k
GND
–6dBv
VM
to AMS Control
∗ Load Impedance 47kΩ
from LINE OUT
R64
100k
DVcc
BIAS
CONTROL
R65
50k
DVcc
PB
PB Amp
REC
[DECK-B]
REC/PB HEAD
Bias
OSC
L1
27mH
C24
75p
REC/PB
GND
C23
150p
C22 R66
3.3µ 12k
to METER IC
AMS OUT
VEE
R62
150
+1.1dBv (1.6V)
Q
BIAS-M
VEE BIAS-C
VEE
Q
Q
BIAS-N
GP CAL
REC CAL
R63
50k
–3dBv
REC OUT
GND GND
R61
56k
R60
10k
Vcc
HEADPHONES
R58
36k
R59
10k
VGS
(C)
+6dBv
VGS
(B)
CALIBRATION
GND Gm4
(A)
C20
100p
C19
100p
Gm3
C18
1.0µ
R57
40k
R56
24k
MT C
GND
R54
14k
R49
10k
GND GND
R48
GND 100k
–6dBv
R45
12k
LINE OUT
L-ch
LINE OUT
C15
0.1µ
R42
2.9k
MUTE
NR
NR/PASS
/MUTE
×1
R53
8k
×1
C17
200p
–7dBv
GND
(A)
GND
–6dBv
R51
20k
R52
20k
(–6dBm)
–7dBv
OFF
METER
DGND
Q
VGS R39
5k
(C)
VGS
(B)
DGND
DVcc DVcc
ON
OFF
VGS
(C)
Gm2
VGS
(C) BPF
–6dBv
–7dBv
NR/PASS/MUTE
VGS
NR
LINE (C)
PASS
–4dBv
MUTE
AMS TC
DET
–11dBv
R40
15k
R43
2.5k
–0.5dBv
R41
20k
METER
ON
ON
CAL
VGS
(B)
ON
CAL
OFF
–7dBv
(–6dBm)
–7dBv
C14
2.2µ
GND
GND
REC IN
REC
VGS
(C)
–24dBv
R38
50k
R37
10k
C13
0.47µ
NR
RECOUT
R34
8.2k
–7dBv
(–6dBm)
R36
1MEG
S SW
–15dBv
AMS
R32
100k
C12
2.2µ
BC/S/CAL
VGS
(C)
×1
CAL
S-NR
B/C-NR
R31
40k
S IN
(–6dBm)
R35
4.7k
Fig. 1. Functional block diagram
C8
0.068µ
NR TCL
VEE
NR TCH
R28
12.5k
LLS VF
ANTS
(–6dBm)
NR OUT
DOLBY S NR
–15dBv
VGS
C10
(B) SUM
106p
R23
40k
R27
40k
for R-ch
HLS VF
Dolby B/C-NR
R22
1.5k
PB
MOA
REC & CAL
R23
PB
REC
REC/PB
OFF
VEE
SSK
C7
0.1µ
ON
VGS
(C)
CAL IN
–26dBv
R21
10k
C8
VGS
(C)
–11dBv
R19
4k
for R-ch
NR
RECIN
C6
2.2µ
R20
2k
VGS
(C)
–26dBv
(–25dBm)
VGS
(C)
–10dBv
VOL OUT
MPX
Filter
GND
METAL
CrO2
NORM
OSC
CXA1878Q
Description of Operation
The CXA1878Q is a Dolby B-C type NR system with a built-in recording/playback equalizer amplifier,
electronic volume, AMS, BIAS SW, and meter circuit. In addition, this chip also contains an S type
(CXA1417S/Q) select switch, enabling the construction of a 2-channel Dolby B-C-S type NR system by using
the CXA1878Q together with two CXA1417S/Q encoder units.
The CXA1878Q has the circuit configuration shown in Fig. 1.
CXA1878Q
1. Reference levels
(1) Recording equalizer amplifier output level (315Hz, –3dBv)
[∗ when the recording equalizer amplifier input level is –24dBv]
(2) Playback equalizer amplifier output level (315Hz, –11dBv)
[∗ when the playback equalizer amplifier input level is –31dBv]
(3) Dolby
The Dolby level is measured at the recording output pin (REC OUT) at –6dBm (388mVrms) in the NR OFF
mode. Reference levels for the recording input pin (LINE IN), playback input pin (PB IN) and line output
pin (LINE OUT) are defined as the levels which apply the Dolby level to REC OUT in the NR OFF mode.
2. System control methods
(1) Mode settings table
Pin No.
Pin voltage
Symbol
Low
Remarks
Medium
High
DOLBY NR ON
C type
3-state
CALIBRATION
3-state
34
NR SW
35
NR S SW
DOLBY S
DOLBY NR ON
B type
DOLBY B-C∗
16
AMS SW
AMS OFF
AMS MODE
BS MODE
3-state
20
MODE SW
PB
—
REC
2-state
19
SPEED
NORMAL SPEED
—
HIGH SPEED
2-state
25
DECK A/B
PB IN A
—
PB IN B
2-state
23
A EQ
PB IN A EQ FLAT
—
PB IN A EQ 70µ
2-state
PB IN B EQ FLAT
PB IN B EQ 70µ
PB IN B EQ 70µ
REC EQ NORMAL
REC EQ CrO2
REC EQ METAL
BIAS SW
NORMAL
BIAS SW
CrO2
BIAS SW
METAL
24
B EQ
DOLBY NR OFF
3-state
17
PASS SW
DOLBY NR
MUTE
PASS
3-state
18
METER SW
METER ON
—
METER OFF
2-state
Note: When 3-state input pins are open, the pin voltage is medium.
∗ The NR SW (Pin 34) operates only when the NR S SW (Pin 35) is set to medium.
(2) Mode setting pin control voltage
3-state
2-state
Control voltage
Min.
Max.
High level
4.2
VCC
Medium level
2.2
2.8
Low level
0.0
0.5
High level
3.5
VCC
Low level
0.0
0.5
– 25 –
CXA1878Q
3. Recording mute function
The CXA1878Q recording mute function is implemented by using a built-in recording mute circuit which varies the
recording equalizer amplifier gain according to the magnitude of the DC voltage applied to the REC MUTE pin
just like an electronic volume control. Also, any desired soft mute or fader can be freely set depending on
momentary changes in the DC voltage applied to the REC MUTE pin. Fig. 2 illustrates the recording mute
waveforms.
Fig. 2. Recording mute waveform
REC MUTE control voltage
Pin No.
Symbol
Pin voltage (V)
0.0
0.5
2.5
4.5
5.0
Remarks
Decrease <<<< Increase
42
REC MUTE Less
than –90
–90
—
—
—
RECOUT attenuation (dB)
NORM Tape, Norm-Speed, f = 1kHz
4. Recording level calibration
The CXA1878Q allows the recording level to be finely adjusted with a DC voltage.
Therefore, the recording level can be varied by approximately ±6dB simply by applying DC voltages of 0 to 5V
(for dual power supply) to the REC CAL pin (Pin 33).
The table below shows the input range of control voltages with the power supplies used.∗1
Output level
Down (Vdown)
REC CAL pin voltage
DGND to 2.5V
Typ.
2.5V∗2
Up (Vup)
2.5V to VCC
∗1 Although the above range of voltages can be input to the control pin, the controllable input voltage range is
as follows.
2.5V < Vup ≤ 5.0V
DGND ≤ Vdown < 2.5V
∗2 Control voltages for this IC are referenced to the DGND pin (Pin 30).
Also note that when not using this recording level calibration function, simply leave the REC CAL pin (Pin 33)
open, so that the voltage of the REC CAL pin is matched to the internal reference voltage (2.5V), with the
recording level set for the standard gain.
– 26 –
CXA1878Q
5. High frequency calibration
The CXA1878Q allows the high frequency response of the recording equalizer to be finely adjusted with a DC
voltage.
Therefore, the recording level in high frequencies (peak) can be varied by approximately ±4dB simply by
applying DC voltages of 0 to 5V (for dual power supply) to the GP CAL pin (Pin 32). The table below shows
the input range of control voltages with the power supplies used.∗3
Output level
Down (Vdown)
GP CAL pin voltage
DGND to 2.5V
Typ.
2.5V∗4
Up (Vup)
2.5V to VCC
∗3 Although the above range of voltages can be input to the control pin, the controllable input voltage range is
as follows.
2.5V < Vup ≤ 5.0V
DGND ≤ Vdown < 2.5V
∗4 Control voltages for this IC are referenced to the DGND pin (Pin 30).
Also note that when not using this high frequency calibration function, simply leave the GP CAL pin (Pin 32)
open, so that the voltage of the GP CAL pin is matched to the internal reference voltage (2.5V), with the
high frequency equalizer amplifier characteristics set for the standard gain.
Gain
[dB]
GP CAL
REC CAL
GP CAL
REC CAL
GP CAL
REC CAL
REC CAL
REC CAL
REC CAL
Frequency [Hz]
Fig. 3. Conceptual diagram of the recording level/high frequency calibration functions
6. Meter circuit
The CXA1878Q has a built-in full-wave rectifier circuit for the level meter. Therefore, a DC voltage can be
obtained by attaching time constants to the METER 1 and 2 output pins. The output voltage is set to 1.6V
(+1.1dBv) during reference input. (for an external time constant of 56kΩ, 33µF)
The MT C pin detects only the AC component. The low frequency cut-off is determined with the capacitor
connected to this pin and the 14kΩ internal resistor. (Approximately 10Hz for 1µF)
7. Recording volume control circuit
The CXA1878Q adjusts the size of the recording signal with a built-in control circuit. Therefore, the gain can be
controlled by applying the voltage between DVCC and DGND to the REC VOL pin (Pin 28).
(A 0dB signal is output when voltage of 2.0V is applied.)
– 27 –
CXA1878Q
8. Recording volume balance circuit
The CXA1878Q contains a circuit which controls the balance between channels 1 and 2 of the recording
volume.
Therefore, the balance between channels 1 and 2 can be controlled by applying the voltage between DVCC
and DGND to the REC BAL pin (Pin 29).
(Signals which are not attenuated by the balance circuit are output from both channels when this control pin is
open or when a voltage of DVCC/2 is applied.)
REC VOL Control Voltage
Pin No.
Symbol
Pin voltage (V)
0.0
0.5
2.0
4.5
5.0
Decrease <<<< Increase
28
REC VOL
Less
than –96
–96
0.0
—
9.0
4.5
5.0
Remarks
VOLOUT1 and 2 attenuation (dB)
BALANCE = 2.5V, f = 1kHz
BALANC control voltage
Pin No.
Symbol
Pin voltage (V)
0.0
0.5
2.5
Remarks
Increase >>>> Decrease
0.0
29
REC BAL
0.0
0.0
–93
VOLOUT2 attenuation (dB)
Less
REC VOL = 5V, f = 1kHz
than –93
Decrease <<<< Increase
Less
than –93
–93
0.0
0.0
0.0
VOLOUT1 attenuation (dB)
REC VOL = 5V, f = 1kHz
9. Bias OSC power supply control circuit
The CXA1878Q contains a switch circuit that selects the supply voltage for the bias oscillator.
The supply voltage can be controlled with the B EQ pin (Pin 24). The maximum output current is 2mA.
– 28 –
CXA1878Q
10. AMS circuit
The CXA1878Q has the music sensor circuit.
DVCC
R3
AMS TC
C3
37
1kΩ
NR PBIN1 62
NR PBIN2 54
36 AMS OUT
COMP
0dB
OP AMP WINDOW
COMP
0dB
16kHz
LPF
100kΩ
G1
R1
[∗2]
G2
R2
[∗1]
[∗1]
C1
C2
[∗2]
Fig. 4. AMS circuit block diagram
(1) AMS ON operation
The signal input from PB NR IN first passes through the LPF, then through the HPF/sensitivity setting
amplifier, and then through the WINDOW comparator where it is formed into a pulse wave. (See Fig. 5)
This signal which has been formed into a pulse wave is integrated by a capacitor connected to the AMS TC
pin (Pin 37) and then input to the comparator. (See Fig. 6)
AMS OUT turns ON when the AMS TC pin voltage falls below the comparator threshold value.
(When the sensitivity changes, the pulse width also changes.)
WINDOW COMP
detection level
(sensitivity)
The broken line shows the case
detection level has changed.
Fig. 5. Conceptual diagram of WINDOW comparator operation
AMS TC pin voltage after integration
COMP detection level
AMS OUT
AMS ON
Fig. 6. Conceptual diagram of AMS OUT operation
– 29 –
CXA1878Q
(2) AMS OFF operation
When the input signal disappears, the capacitance connected to the AMS TC pin (Pin 37) is discharged,
causing the TC pin voltage to rise above the threshold value and turn AMS OFF.
(3) AMS gain setting method
The AMS gain (G1/G2 mode gain) adjustment can be determined by external resistances R1 and R2.
In addition, AMS gain is expressed by the following equations.
G1 = 20 log
R1 + 100kΩ (internal resistance)
dB
R1
G2 = 20 log
R2 + 100kΩ (internal resistance)
dB
R2
dB
[∗2]
[∗1]
G1 NOR (BS)
G2 FF (AMS)
[∗2]
[∗1]
Frequency
(4) AMS low frequency cut-off setting method
The AMS low frequency cut-off adjustment can be determined by external resistances R1 and R2 and
capacitances C1 and C2.
(5) Relationship between response time and sensitivity
The AMS ON time is determined by the width of the pulse obtained by applying the input signal to the
WINDOW comparator. The pulse emitted from the WINDOW comparator becomes extremely small near
the detection level, and some time is required for this pulse to be integrated by the external capacitance,
thus lengthening the response time.
∗ Response times can be adjusted to approximately the same value by adjusting the AMS sensitivity with
resistances R1 and R2 to match the various ICs. Also, the AMS OFF time is determined by the external
time constant (R3, C3).
Notes on Operation
Temperature characteristics and accuracy of the recording equalizer amplifier
The temperature characteristics of the built-in monolithic filter and the filter cut-off frequency depend on the
27kΩ external resistance connected to the IREF pin (Pin 10). Also, the recording equalizer amplifier
frequency response depends on unevenness in the absolute, as well as relative values of the internal
capacitance. Furthermore, the high frequency response indicates a high element sensitivity at the filter
because the band-pass filter Q is high. Compared to low frequency, although the unevenness inherent in
the IC is more likely to occur, this occurs relatively, and not individually for channels 1 and 2.
– 30 –
CXA1878Q
Example of Representative Characteristics
Recording equalizer amplifier frequency response
(NORMAL SPEED)
Recording equalizer amplifier frequency response
(HIGH SPEED)
30.0
20.0
VCC, VEE = ±7.0V
0dB = NORM - NORM, 315Hz, –23dBv (Output reference)
(Tape) (Speed)
NORM - NORM
CrO 2 - NORM
METAL - NORM
Output response [dB]
Output response [dB]
30.0
10.0
0.0
20.0
VCC, VEE = ±7.0V
0dB = NORM - NORM, 315Hz, –23dBv (Output reference)
(Tape) (Speed)
NORM - HIGH
CrO 2 - HIGH
METAL - HIGH
10.0
0.0
–10.0
–10.0
100
1k
10k
100k
100
Frequency [Hz]
Output level vs. REC CAL pin voltage
8
8
315Hz
8kHz
6
4
2
0
VCC, VEE = ±7.0V
(Tape) (Speed)
MODE: NORM - NORM
GP CAL pin = Open
0dB = REC CAL and
GP CAL pin = Open
–20dB (at 315Hz,–3dBv)
–2
–4
–6
4
2
0
–2
–4
–6
–2.0 –1.0 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0
REC CAL and GP CAL frequency response
Output response [dB]
10.0
0.0
VCC, VEE = ±7.0V
(Tape) (Speed)
0dB = NORM - NORM, 315Hz, –23dBv (Output reference)
REC CAL and GP CAL = Open
GP = 5.0V
2.5V
0.0V
REC CAL = 5.0V
REC CAL = 2.5V
REC CAL = 0.0V
–10.0
100
1k
A
AAAA
AA
VCC, VEE = ±7.0V
(Tape) (Speed)
MODE: NORM - NORM REC CAL pin = Open
0dB = REC CAL pin and GP CAL pin = Open
–20dB (at 315Hz,–3dBv)
GP CAL pin voltage [V]
40.0
20.0
315Hz
3kHz
8kHz
12kHz
–2.0 –1.0 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0
REC CAL pin voltage [V]
30.0
10k
Output level vs. GP CAL pin voltage
Output level [dB]
Output level [dB]
6
1k
Frequency [Hz]
10k
100k
Frequency [Hz]
– 31 –
100k
CXA1878Q
Output level vs. REC MUTE pin voltage 1
Output level vs. REC MUTE pin voltage 2
100
0
80
Output level [dB]
Output level [%]
–20
60
40
VCC, VEE = ±7.0V
(Tape) (Speed)
MODE: NORM - NORM,
0dB = 1kHz, +12dB
(at 315Hz, –3dBv)
f = 1kHz
20
0
VCC, VEE = ±7.0V
(Tape) (Speed)
MODE: NORM - NORM,
0dB = 1kHz, +12dB
(at 315Hz, –3dBv)
f = 1kHz
–40
–60
–80
0.0 1.0 2.0 3.0 4.0 5.0 6.0
0.2
REC MUTE pin voltage [V]
1.0
2.0
5.0
Recording equalizer amplifier load characteristics
Output level vs. REC MUTE pin voltage 3
15
Maximum output level (dB)
0
–20
Output level [dB]
0.5
REC MUTE pin voltage [V]
–40
–60
–80
10
0
VCC, VEE = ±7.0V
(Tape) (Speed)
MODE: NORM - NORM,
0dB = 1kHz, +12dB
(at 315Hz, –3dBv)
f = 1kHz
–100
VCC, VEE = ±7.0V
(Tape) (Speed)
MODE: NORM - NORM,
0dB = –3dBv (REC OUT pin)
THD + N = 1%
315Hz
1kHz
5
100
1k
10k
100k
Load resistance RL [W]
Recording volume balance characteristics
0.0 1.0 2.0 3.0 4.0 5.0 6.0
0
REC MUTE pin voltage [V]
–10
Recording volume output level [dB]
Recording volume characteristics
0
Volume output [dB]
–10
–20
–30
–40
–50
–60
–70
VCC, VEE = ±7.0V
DVCC = +5.0V
Input : VOLUME IN = –10dBv, f = 1kHz
REC BAL pin voltage = 2.5V
0.5
1.0
2.0
–30
–40
–50
–60
–70
VCC, VEE = ±7.0V
DVCC = +5.0V
Input : VOLUME IN = –10dBv,
f = 1kHz
REC VOL pin voltage = +5.0V
1CH
2CH
–80
–90
–100
–80
0.2
–20
0.0
5.0
1.0
2.0
3.0
4.0
Balance control pin voltage [V]
REC LEVEL pin voltage [V]
– 32 –
5.0
CXA1878Q
Meter rectification output characteristics
Level meter output characteristics (REC, PB mode)
+13dB
1.0
0.1
VCC, VEE = ±7.0V
DVCC = +5.0V
PB mode:
0dB = –4dBv
(LINE OUT)
REC mode:
0dB = –7dBv
(NR REC OUT)
f = 1kHz
0.01
–60
–40
–20
0dB
1
–10dB
–20dB
0.1
–30dB
–40dB
Playback equalizer amplifier distortion
10
1.0
T.H.D + N [%]
Playback equalizer amplifier frequency response
25.0
120µs
17.0
10k
Frequency [Hz]
0
21.0
1k
100
20
Input level [dB]
Output response [dB]
+10dB
VCC, VEE = ±7.0V
0dB = –7dBv (NR REC OUT)
Rectification voltage [V]
Meter output voltage [V]
5.0
VCC, VEE = ±7.0V
(Tape) (Speed)
MODE = NORM - NORM
100Hz
1kHz
10kHz
0.1
70µs
60µs
13.0
9.0
VCC, VEE = ±7.0V
(Tape) (Speed)
0dB = NORM - NORM, 315Hz, –31dBv
(input reference)
0.01
35µs
–30
–40
5.0
–20
–10
Input level [dBv]
100
1k
10k
100k
Line amplifier THD + N
Frequency [Hz]
10.0
Line amplifier frequency response (PASS mode)
10.0
Output response [dB]
1.0
VCC, VEE = ±7.0V
MODE = PASS MODE
0dB = –4dBv (LINE OUT)
100Hz
1kHz
10kHz
8.0
6.0
0.1
4.0
2.0
0.0
VCC, VEE = ±7.0V
0dB = –11dBv (NR PB IN)
PASS mode
100
1k
0.01
10k
100k
Frequency [Hz]
–16 –12 –8
–4
0
4
Output level [dB]
– 33 –
8
12
16
CXA1878Q
A.M.S/B.S mode frequency response
VCC, VEE = ±7.0V
0dB = –11dBv
AMS mode
BS mode
Input level [dB]
20
10
0
–10
–20
–30
100
1k
Frequency [Hz]
10k
BIAS SW load characteristics
–6.4
Output voltage [V]
–6.5
–6.6
–6.7
–6.8
VCC, VEE = ±7.0V
–6.9
BIAS N
BIAS C
BIAS M
–7.0
0
0.5
1.0
1.5
2.0
Output current [mA]
Current consumption [mA]
Supply voltage vs. Current consumption
38
37
36
35
34
5.0
6.0
7.0
Supply voltage [V]
– 34 –
8.0
CXA1878Q
Dolby B type NR encode boost
10
VCC, VEE = ±7V
Dolby Level 400Hz, –6dBm
Dolby C type NR encode boost
–40dB
20
–60dB
–55dB
–50dB
–45dB
–40dB
–35dB
8
Encode Boost [dB]
Encode Boost [dB]
–35dB
–30dB
6
–25dB
4
–20dB
–15dB
–10dB
–5dB
0dB (Dolby Level)
2
0
16
12
8
–30dB
4
–25dB
–2
–4
1k
100
–20dB
–15dB
–10dB
–5dB
0dB (Dolby Level)
0
VCC, VEE = ±7V
Dolby Level 400Hz, –6dBm
10k
Frequency [Hz]
100
1k
10k
Frequency [Hz]
Dolby NR OFF total harmonic distortion
T.H.D + N [%]
VCC, VEE = ±7.0V
0dB = –6dBm (NR REC OUT, NR OFF)
Encode Mode
100Hz
1kHz
1
10kHz
0.1
0.01
–4
0
4
8
12
16
20
Output level [dB]
Dolby C type NR total harmonic distortion
Dolby B type NR total harmonic distortion
100Hz
1kHz
10kHz
1
T.H.D + N [%]
T.H.D + N [%]
VCC, VEE = ±7.0V
0dB = –6dBm (NR REC OUT, NR OFF)
Encode Mode
100Hz
1kHz
1
10kHz
0.1
0.01
0.1
0.01
–4
0
4
8
12
16
20
VCC, VEE = ±7.0V
0dB = –6dBm (NR REC OUT, NR OFF)
Encode Mode
–4
Output level [dB]
0
4
8
12
Output level [dB]
– 35 –
16
20
CXA1878Q
Package Outline
Unit: mm
64PIN QFP(PLASTIC)
23.9 ± 0.4
+ 0.4
20.0 – 0.1
+ 0.1
0.15 – 0.05
51
0.15
64
20
1
16.3
32
+ 0.4
14.0 – 0.1
52
17.9 ± 0.4
33
+ 0.2
0.1 – 0.05
0.8 ± 0.2
19
+ 0.35
2.75 – 0.15
+ 0.15
0.4 – 0.1
1.0
± 0.12 M
PACKAGE STRUCTURE
PACKAGE MATERIAL
EPOXY RESIN
SOLDER/PALLADIUM
PLATING
SONY CODE
QFP–64P–L01
LEAD TREATMENT
EIAJ CODE
QFP064–P–1420
LEAD MATERIAL
42/COPPER ALLOY
PACKAGE MASS
1.5g
JEDEC CODE
– 36 –