SONY CXA1704R

CXA1704R
2-channel REC/PB Amplifier for 8mm VCR
Description
The CXA1704R is a bipolar IC designed as a
recording/playback amplifier for Hi8-compatible
VCRs.
Features
O Recording system
• Feedback damping provided in the recording
amplifier and its EVR control function facilitate
circuit board design.
• Y, chroma, and low-band level adjustment
functions
• Ramp circuit
O Playback system
• Feedback damping provided in the playback
amplifier facilitates circuit board design.
• Middle-frequency tuner on chip; EVR permits
independent adjustment of f0, Q and boost
• RF AGC and dropout detection circuit
48 pin LQFP (Plastic)
Absolute Maximum Ratings (Ta=25°C)
• Supply voltage
VCC
7
V
• Operating temperature Topr
–10 to +75
°C
• Storage temperature
Tstg –65 to +150 °C
• Allowable power dissipation
PD
1100
mW
(when board is mounted)
Operating Conditions
Supply voltage
+0.5
V
VCC
4.75
–0.25
Structure
Bipolar silicon monolithic IC
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—
E93860A66-TE
CXA1704R
24
23
22
21
20
19
18
17
16
15
MTG1
MTOUT
MTG2
PCMOUT
MTF0
RP_PB
VCC
T1
RFSWP
T2
T3
MTQ
Block Diagram and Pin Configuration
14
13
VCC1
DOP
1CH
2CH
MUTE
REC1CONT
26
MTGSW
25
PCMSW
12
DOCDET
11
RAMP
GEN
REC
REC1OUT
RFAGCIN
V/I
27
1CH(0dB)
1CH(6dB)
2CH(0dB)
2CH(6dB)
MUTE
40dB
PB1IN
HEAD
28
M•T
–6dB
15dB
10
12dB
VIDEOSW
9
DOCDET
GND1
AGCDET
29
8
RFAGCTC
RFAGCOUT
RF
AGC
PBDUMP1
30
7
31
6
PBDUMP2
YLEVEL
YIN
GND2
HEAD
32
LOWLEVEL
15dB
5
40dB
PB2IN
CIN
33
1
V/I
REC2OUT
PCM
4
1
YGCA
REC
34
CGCA
1
VIDEO
VPSW1
XGAIN
LOWGCA
3
1
RAMP
GEN
1
REC2CONT
VPSW2
VIDEO
35
AFMIN
1
2
LOWGCA
PCM
2
VCC2
CCONT
36
1
—2—
48
ATFIN
47
PCMREC
46
PCMIN
45
VG2
44
IR
43
IR1
42
GND
41
VPSW1OUT
40
REC1IN
39
VREG
38
VPSW2OUT
REC2IN
37
CXA1704R
Pin Description
Pin No.
CCONT
Pin voltage
Equivalent circuit
Description
EVR adjustment of recording
chroma level.
Gain is small when the applied
voltage is large.
—
270
32.5k
1
Symbol
143
1
67.5k
25k
2
AFMIN
90µ 90µ
Recording AFM input.
DC is cut off by internal capacitor.
Input level is 125 mVp-p (typ.).
When not used, connect this pin to
Vcc.
—
60µ
20p 143
50k
2
3
XGAIN
VIDEO SW gain switch.
Low : 6 dB
High : 0 dB
—
35µ
143
3
CIN
Recording chroma input.
Input the signal with capacitor
coupling.
Input level is 300 mVp-p (typ.).
2.4 V
70µ
143
4
50k
4
—3—
CXA1704R
Pin No.
LOW LEVEL
Pin voltage
Equivalent circuit
Description
—
270
33.5k
5
Symbol
143
5
66.5k
21k
6
YIN
90µ
90µ
2.4 V
EVR adjustment of recording RF
signal level.
Gain is small when the applied
voltage is large.
Adjusts both the VIDEO path and
the PCM path simultaneously.
VIDEO path:
Adjustment of C + AFM + ATF
PCM path: Adjustment of ATF
Recording Y signal input.
Input the signal with capacitor
coupling.
Input level is 500 mVp-p (typ.).
40µ
143
50k
6
YLEVEL
—
EVR adjustment of recording Y
signal level.
The Y LEVEL is small when the
applied voltage is large.
270
32.5k
7
143
67.5k
23k
8
RFAGCOUT
7
90µ 90µ
2.8 V
Playback Y signal output.
Output level is 380 mVp-p (typ.).
40µ
8
600µ
—4—
CXA1704R
Pin No.
9
Symbol
RFAGCTC
Pin voltage
Equivalent circuit
Description
—
RF AGC time constant.
143
9
25µ
10
RFAGCIN
25µ
25µ
—
RF AGC input of playback Y level.
The playback video signal output
from Pin 14 (MTOUT) passes
through an external ATF TRAP,
AFM TRAP, and C TRAP, and is
then input to Pin 10 (RFAGCIN)
again.
DC is cut off by internal capacitor.
When not used, connect this pin to
Vcc.
13p 143
50µ
DOCDET
2.5 V
Determines the dropout detection
level.
47k
11
50k
10
143
Dropout detection signal output.
Goes high when a dropout is
detected.
150
64k
12
2.4k
H: 3.1 V
L: 0 V
100k
DOP
72k
12
46.5k
50µ
79k
11
—5—
CXA1704R
MTG1
Pin voltage
Equivalent circuit
Description
—
40k
13
Symbol
270
Pin No.
143
13
REVR adjustment of channel 1
middle-frequency tuner boost.
Boost is small when the applied
voltage is large.
58k
14k
14
MTOUT
90µ 90µ
2.4 V
Playback VIDEO output.
Y + C + AFM + ATF is output.
40µ
14
400µ
—
EVR adjustment of channel 2
middle-frequency tuner boost.
Boost is small when the applied
voltage is large.
270
MTG2
40k
15
143
15
58k
14k
16
PCMOUT
90µ 90µ
2V
Playback PCM output.
40µ
16
400µ
—
EVR adjustment that determines f0
of the middle-frequency tuner. f0 is
large when the applied voltage is
large.
270
33k
MTF0
143
17
41k
60k
17
40µ
40µ
—6—
CXA1704R
Pin No.
Symbol
Pin voltage
18
RP_PB
—
Equivalent circuit
35µ
Description
REC/PB switch.
High : PB
Low : REC
35µ
143
18
19
VCC
4.75 V
20
T1
—
Power supply for sections other
than the REC amplifier and the PB
amplifier.
Connect to GND.
35µ
35µ
143
20
21
RFSWP
—
RFSWP input.
35µ
35µ
143
21
22
T2
—
Connect to GND.
35µ
35µ
143
22
—7—
CXA1704R
Pin No.
23
Symbol
T3
Pin voltage
Equivalent circuit
Description
—
Connect to GND.
35µ
35µ
143
23
—
270
MTQ
30k
24
143
24
47k
50k
40µ
4.75 V
—
Channel 1 power supply.
EVR adjustment of recording
channel 1 damping
Damping is applied strongly when
the applied voltage is small.
270
VCC1CH
REC1CONT
34k
25
26
40µ
143
26
66k
71k
40µ
—
Recording channel 1 output.
Open collector.
16.5k
—8—
30
27
1k
REC1CONT
5.7k
27
40µ
EVR adjustment that determines Q
of the middle-frequency tuner. Q is
large when the applied voltage is
large.
CXA1704R
Pin No.
PB1IN
Pin voltage
Equivalent circuit
Description
0.7 V
Playback channel 1 input.
2.5k
28
Symbol
28
GND1CH
PBDUMP1
0V
2.5 V
40µ
270
29
30
30
4k
Channel 1 GND.
The playback channel 1 damping is
determined by the external
resistance. Damping is applied
strongly when the resistance is
large.
4k
4k
40µ
PBDUMP2
2.5 V
40µ
270
31
31
4k
The playback channel 2 damping is
determined by the external
resistance. Damping is applied
strongly when the resistance is
large.
4k
4k
40µ
32
GND2CH
0V
Channel 2 GND.
—9—
CXA1704R
Symbol
Pin voltage
33
PB2IN
0.7 V
Equivalent circuit
Description
Playback channel 2 input.
2.5k
Pin No.
33
REC2OUT
—
Recording channel 2 output.
Open collector.
16.5k
34
30
—
EVR adjustment of recording
channel 2 damping. Damping is
applied strongly when the applied
voltage is small.
270
REC2CONT
34k
35
1k
5.7k
34
143
35
66k
71k
4.75 V
2.4 V
143
240µ
—10—
50k
1.3k
1.3k
37
50k
VCC2CH
REC2IN
10p
36
37
40µ 40µ
Channel 2 power supply.
Channel 2 recording amplifier input.
DC cut-off is applied to the Pin 38
signal by external capacitor, and
then the resulting signal is input.
CXA1704R
Pin No.
Symbol
Pin voltage
38
VPSW2OUT
2.4 V
Equivalent circuit
Description
Recording channel 2 VPSW output.
Output level is 200 mVp-p (typ.).
40µ
38
400µ
VREG
4.15 V
4.15 V regulator output.
10k
39
5p
39
40
REC1IN
2.4 V
143
10p
41
VPSW1OUT
50k
1.3k
1.3k
50k
40
Channel 1 recording amplifier input.
DC cut-off is applied to the Pin 41
signal by external capacitor, and
then the resulting signal is input.
240µ
2.4 V
Recording channel 1 VPSW output.
Output level is 200 mVp-p (typ.).
40µ
41
400µ
—11—
CXA1704R
Symbol
Pin voltage
42
GND
0V
43
IR1
1.9 V
Equivalent circuit
Description
GND for sections other than the
REC amplifier and the PB amplifier.
Determines the REC amplifier gain.
Generates the reference current
when 15 k Ω resistance is inserted
to GND.
Insert 18 k Ω resistance to GND.
42k
Pin No.
40k
1k
20k
43
40µ
IR
1.9 V
Generates the reference current for
the middle-frequency tuner, dropout
detection circuit, and the ramp.
42k
44
40k
1k
20k
2.45 V
2.45 V internal reference voltage
source.
270
VG2
34.5k
45
44
40µ
20k
49k
4k
45
PCMIN
2.4 V
Recording PCM input.
Input the signal with capacitor
coupling.
Input level is 300 mVp-p (typ.).
70µ
143
46
50k
46
75µ
—12—
CXA1704R
Pin No.
Symbol
Pin voltage
47
PCMREC
—
Equivalent circuit
Description
PCM recording switch.
PCM recording is selected when
high.
35µ
35µ
143
47
ATFIN
2.4 V
Recording ATF input.
Input the signal with capacitor
coupling.
Input level is 125 mVp-p (typ.).
70µ
143
48
50k
48
—13—
3
6
Gymax
YGCA maximum gain
7
8
—14—
15
14
13
12
11
10
path) minimum gain
Low-frequency GCA (PCM
path) maximum gain
Low-frequency GCA (VIDEO
path) maximum gain
Low-frequency GCA (VIDEO
path) center gain
Low-frequency GCA (VIDEO
path) minimum gain
Low-frequency GCA (VIDEO
center gain
YGCA secondary distortion
(center gain)
Glpmin
Glvmax
Glvmax 2
Glvcen
Glvmin
DY
48
48
2
2
2
6
6
6
Gycen
YGCA center gain
6
∆Y
6
Gymin
YGCA minimum gain
5
YGCA frequency response
—
—
9
—
—
Vg2 pin voltage
—
Vreg pin voltage
—
Ipb
—
Input pin
Ib1,Ib2
Irec
Symbol
4
playback
Current consumption for
2
recording
Current consumption for
Recording amplifier bias current
1
No.
Item
Electrical Characteristics
125mVp-p
125mVp-p
125mVp-p
125mVp-p
125mVp-p
500mVp-p
500mVp-p
200mVp-p
500mVp-p
500mVp-p
—
—
—
—
—
Level
100kHz
100kHz
1.7MHz
1.7MHz
1.7MHz
7MHz
300kHz
14MHz
300kHz
300kHz
300kHz
—
—
—
—
—
Frequency
Input conditions
Measurement conditions
A
A
A
A
A
A
A
A
A
A
A
A
A
D
YLEVEL = Vylev
Pin 5 LOWLEVEL = Vcc
YLEVEL = Vylev
Pin 5 LOWLEVEL = 1.8 V
YLEVEL = Vylev
Pin 5 LOWLEVEL = 1.8 V
YLEVEL = Vylev
is 12.5 mVp-p (Vylev).
Adjust Pin 5 LOWLEVEL so that the output
YLEVEL = Vylev
Pin 5 LOWLEVEL = Vcc
YLEVEL = Vylev
YLEVEL = Vylev
Level at 14 MHz/level at 300 kHz
Pin 7 YLEVEL = 1.8 V
200 mVp-p (Vylev).
Adjust Pin 7 YLEVEL so that the output is
Pin 7 YLEVEL = Vcc
Measure the pin voltage.
Measure the pin voltage.
channel playback.
Measure the current consumption for two-
Measure the DC current.
channel recording (includes bias current).
Measure the current consumption for two-
Measurement method
63
Typ.
82
Max.
-8
- 20
—
—
—
- 32.0 - 26.0
- 14.0 - 12.4
—
—
0
—
—
- 32.0 - 26.0
- 14.0 - 12.4
—
—
- 53
- 1.5 - 0.8
—
2.60
4.35
46
- 15.8 - 14.1
2.45
4.15
35
- 2.2 - 1.1
—
—
2.30
3.95
24
14.55 18.8 23.05
44
Min.
dB
V
mA
Unit
∗ For details on the control logic, refer to the Control Logic Truth Table.
41, 38
41, 38
41, 38
41, 38
41, 38
41, 38
41, 38
41, 38
41, 38
41, 38
45
39
Ivcc
Ib1, Ib2
Ivcc
ammeter name
logic
A
pin or
Control
Measurement
(Vcc = 4.75 V, Ta = 25°C ; Refer to the Electrical Characteristics Measurement Circuit.)
CXA1704R
Item
—15—
Gpcm
Vagc1
Vagc2
Vagc3
30 RFAGC standard output
31 Cover range high
32 Cover range low
Gmt2
28 PBMTOUT gain (XGAIN = low)
29 PBPCMOUT gain
Gmt1
∆r1, ∆r2
Ir1, Ir2
27 PBMTOUT gain (XGAIN = high)
response
26 Recording amplifier frequency
current
25 Recording amplifier output
distortion
24 PCM main path secondary
DP
10
10
10
28, 33
28, 33
28, 33
40, 37
40, 37
46
46
∆P
23 PCM main path frequency
response
46
Gp
22 PCM main path gain
secondary distortion
1.2Vp-p
50mVp-p
224mVp-p
200µVp-p
200µVp-p
200µVp-p
200mVp-p
200mVp-p
300mVp-p
300mVp-p
300mVp-p
300mVp-p
7MHz
7MHz
7MHz
300kHz
300kHz
300kHz
1MHz
10MHz
1MHz
7MHz
300kHz
300kHz
2MHz
4
21 Chroma GCA center gain
2MHz
300kHz
300kHz
300kHz
100kHz
Frequency
300kHz
300mVp-p
300mVp-p
300mVp-p
300mVp-p
125mVp-p
Level
Input conditions
response (center gain)
DC
4
∆C
20 Chroma GCA frequency
4
Gcmax
19 Chroma GCA maximum gain
4
Gccen
18 Chroma GCA center gain
4
48
Input pin
Gcmin
Glvp
Symbol
17 Chroma GCA minimum gain
path) maximum gain
16 Low-frequency GCA (PCM
No.
Measurement conditions
14
14
16
8
8
8
F, G
D, E
D
D
D
27, 34
27, 34
41, 38
41, 38
41, 38
41, 38
D, E
A
A
B, C
B, C
B, C
A
41, 38
41, 38
A
A
41, 38
A
41, 38
A
41, 38
ammeter name
logic
A
pin or
Control
Measurement
↓
Measure the output level.
MTG1, MTG2 = Vcc
Level at 10 MHz/level at 1 MHz
Output level (V)/51 (Ω)
REC1CONT, REC2CONT = 3.3 V
Level at 14 MHz/level at 300 kHz
YLEVEL = Vylev, LOWLEV = Vllev
YLEVEL = Vylev, LOWLEV = Vllev
Level at 2 MHz/level at 300 kHz
YLEVEL = Vylev, LOWLEV = Vllev
Pin 1 CCONT = 1.8 V
YLEVEL = Vylev, LOWLEV = Vllev
50 mVp-p (Vclev)
Adjust Pin 1 CCONT so that the output is
YLEVEL = Vylev, LOWLEV = Vllev
Pin 1 CCONT = Vcc
YLEVEL = Vylev
Pin 5 LOWLEVEL = 1.8 V
Measurement method
- 15.6
- 50
0
—
+0.5
—
—
- 55
- 0.2
—
305
335
420
345
380
57.5 61.0
63.5 67.0
57.5 61.0
—
17.7 20.0
—
- 1.5 - 0.8
dB
Unit
530
—
420
64.5
70.5
64.5
—
mVp-p
dB
22.3 mAp-p
—
0
- 4.5 - 3.5 - 2.5
—
- 0.5
—
- 24.0 - 21.6
- 13.3 - 11.0
—
—
- 14.0 - 12.4
Min. Typ. Max.
CXA1704R
Input pin
Level
Frequency
Input conditions
D
D
D
Vdop-l
Vdop-h
Tdop-on
Tdop-off
Dropout pulse low level
Dropout pulse high level
Dropout ON detection time
Dropout OFF detection time
35
36
37
38
(diagram at right).
Refer to the measurement method
D
D
Kdop-off
Dropout detection OFF level
(diagram at right).
12
12
12
12
12
12
ammeter name
logic
D
pin or
Measurement
Control
34
Kdop-on Refer to the measurement method
Symbol
Dropout detection ON level
Item
33
No.
Measurement conditions
—16—
a
VDOP-L
VDOP-H
b 224mVp-p
7MHz
Pin 12 DOP
7M/224mVp-p
Pin 10 RFAGCIN
5kHz
50µs
a
224
Kdop-off = 20log b
224
Kdop-on = 20log
Tdop-on Tdop-off
Pin 12
DOP
10kHz
Pin 10 RFAGCIN
Measurement method
Typ.
Max.
—
—
2.9
0
2
1
3.1
0.01
- 10.2 - 7.2
—
—
3.3
0.2
- 4.2
- 15.0 - 12.0 - 9.0
Min.
µs
V
dB
Unit
CXA1704R
CXA1704R
Control Logic Truth Table
Control logic input
Input
conditions
and operation
Operation of each section for the input conditions shown at left
conditions
Pin 14
Pin 8
Dropout detection circuit
×
×
×
×
×
VIDEO REC
B
L
L
H
—
P
V
P
V
×
×
×
×
×
×
PCM REC
C
L
H
H
—
V
P
V
P
×
×
×
×
×
×
↓
D
H
L
L
H
×
×
×
×
O
O
CH1 CH2
O
O
PB
E
H
H
L
H
×
×
×
×
O
O
CH2 CH1
O
O
↓
F
H
L
L
L
×
×
×
×
O
O
CH1 CH2
O
O
↓
G
H
H
L
L
×
×
×
×
O
O
CH2 CH1
O
O
↓
Pin 47
Pin 21
Pin 18
Explanation of input conditions:
H : Control logic input voltage is 2.3 V or more.
L : Control logic input voltage is 0.6 V or less.
— : Don’t care.
RFAGCOUT
Pin 16
×
MTOUT
PB2chAmp
V
PCMOUT
PB 1chAmp
V
REC2OUT
Pin 34
V
REC1OUT
Pin 27
V
VPSW2OUT
Pin 38
—
VPSW1OUT
L
XGAIN
—
PCMREC
L
Control logic
conditions
RFSWP
A
RP_PB
Pin 41
Playback system
Pin 3
Recording system
Operation
Explanation of operation symbols:
O
: Operates.
V
: VIDEO signal is selected.
X
: Does not operate.
P
: PCM signal is selected.
CH1 : CH1 signal is output.
CH2 : CH2 signal is output.
Explanation of Measurement Methods
Playback system signal input method
50Ω
49Ω
5.6µH
0.01µF
PB IN pin
1Ω
CXA1704
head amplifier
Signal source
Middle-frequency tuner measurement method
As shown in the diagram at right, assume f0 = 8
MHz, Q = 2.5, and the boost = 6 dB as the center
conditions. Fix two of them at their respective
center condition, and apply the EVR control of the
adjustment item to measure the adjustment
range.
Boost =6dB
fo = 8MHz
Q = 2.5
—17—
Mode
REC
PB
VCC
4.75V
A IVCC
PB2IN
PB1IN
5.6µ
Ib1
100µ
0.1µ
10µ
Ib2
VCC2
REC2CONT
51 ∗
REC2OUT
0.01µ
PB2IN
GND2
390
PBDUMP2
390
PBDUMP1
GND1
0.01µ
PB1IN
51 ∗
REC1OUT
REC1CONT
5.6µ
0.022µ
0.022µ
REC2CONT
49
49
REC1CONT
1
1
36
35
34
33
32
31
30
29
28
27
26
MTQ
37
REC
38
40dB
HEAD
HEAD
40dB
REC
0.01µ
25
51 VPSW2OUT
MTQ
REC2IN
T3
VPSW2OUT
39
RAMP
GEN
V/I
15dB
15dB
V/I
RAMP
GEN
40
21
RFSWP
0.01µ
T2
VREG
10µ
10µ
REC1IN
RFSWP
REC1IN
22
51 VPSW1OUT
41
1CH
2CH
MUTE
19
0.1µ
42
PCM
43
YGCA
VIDEOSW
VIDEO
PCM
18
PCMSW
VIDEO
1CH(0dB)
1CH(6dB)
2CH(0dB)
2CH(6dB)
MUTE
VPSW2
VPSW1
20
T1
VPSW1OUT
REC2IN
10µ
GND
RP PB
15k ∗
VCC
10µ
RP_PB
IR1
44
2
1
17
MTF0
IR
MTF0
18k ∗
23
RF
AGC
1
45
M•T
–6dB
1
PCMOUT
12dB
15
MTG2
46
LOWGCA
LOWGCA
AGCDET
16
0.1µ
24
PCMIN
VCC1
1
1
0.01µ
PCMOUT
VG2
10µ
MTGSW
MTG2
PCMIN
0.1µ
MTOUT
47
1
13
48
CGCA
DOCDET
14
ATFIN
100µ
51
PCMREC
MTOUT
PCMREC
MTG1
MTG1
ATFIN
—18—
1
2
3
4
5
6
7
8
9
10
11
12
CCONT
AFMIN
XGAIN
0.01µ
CIN
LOWLEVEL
0.01µ
YIN
YLEVEL
RFAGCOUT
RFAGCTC
0.01µ
RFAGCIN
DOCDET
DOP
51
51
51
51
CCONT
AFMIN
XGAIN
CIN
LOWLEVEL
YIN
YLEVEL
Resistance accuracy: 1%
Control logic pin
EVR adjustment pin
Signal input pin
Signal output pin
RFAGCOUT
4700p
470k
RFAGCIN
DOP
∗
0.1µ
Electrical Characteristics Measurement Circuit
CXA1704R
51
0.01µ
CH1 HEAD
PBDUMP2
100µ
VCC2
REC2CONT
REC2OUT
0.01µ
PB2IN
GND2
390 0.022µ
0.1µ
10µ
PBDUMP1
GND1
0.01µ
PB1IN
REC1OUT
REC1CONT
VCC1
390 0.022µ
10µ
0.1µ
36
35
34
33
32
31
30
29
28
27
26
25
REC1CONT
37
REC
0.01µ
40dB
40dB
38
HEAD
HEAD
REC
23
RFSWP
39
RAMP
GEN
V/I
15dB
15dB
V/I
RAMP
GEN
22
RP PB
10µ
REC2IN
REC2CONT
MTQ
24
40
21
0.01µ
41
1CH
2CH
MUTE
19
42
PCM
43
YGCA
VIDEOSW
VIDEO
PCM
18
PCMSW
VIDEO
1CH(0dB)
1CH(6dB)
2CH(0dB)
2CH(6dB)
MUTE
VPSW2
VPSW1
20
10µ
44
2
1
17
1
1
RF
AGC
M•T
–6dB
45
12dB
15
46
LOWGCA
LOWGCA
AGCDET
16
1
1
47
1
13
0.01µ
48
CGCA
DOCDET
14
AFM TRAP
0.01µ
1
2
3
4
5
6
7
8
9
10
11
12
0.01µ
0.01µ
CCONT
AFMIN
XGAIN
CIN
LOWLEVEL
YIN
YLEVEL
RFAGCOUT
RFAGCTC
RFAGCIN
DOCDET
DOP
ATF TRAP
4700p
470k
C TRAP
RF EQ
RFGND
PCMREC
XGAIN
PCMIN
ATFIN
AFMIN
CIN
YIN
EVR
LOGIC
SIGNAL IN
LOWLEVEL
CCONT
YLEVEL
MTG1
MTG2
MTF0
MTQ
DOP
RFVCC
RFAGCOUT
PCM OUT SIGNAL OUT
PB C RF
PB RF
Application circuits shown are typical examples illustrating the operation of the devices. Sony cannot assume responsibility for any problems arising out of the use of these circuits
or for any infringement of third party and other right due to same.
CH2 HEAD
100µ
VREG
T3
VPSW2OUT
T2
0.1µ
RFSWP
REC1IN
T1
VPSW1OUT
100µ
GND
LOGIC
15k
VCC
0.1
µ
RP_PB
IR1
MTF0
IR
MTG1
EVR
18k
PCMOUT
VG2
0.1µ
MTOUT
PCMREC
MTG2
MTGSW
PCMIN
10µ
—19—
ATFIN
Application Circuit
CXA1704R
CXA1704R
Description of Operation
<Recording level adjustment + SW>
After the recording level is adjusted so that the current level of the Y, chroma, AFM, ATF, and PCM signals are
suitable at the head, the VIDEO + ATF and PCM + ATF signals are created and output to the CH1 and CH2
output pins with the proper timing.
The Y level adjustment is made by Pin 7 (YLEVEL), the low frequency level adjustment is made by Pin 5
(LOWLEVEL), and the chroma level adjustment is made by Pin 1 (CCONT). LOWGCA for the VIDEO path and
the PCM path is also adjusted accordingly.
The gain values shown in the specifications are all I/O gain values.
<Recording amplifier>
This performs V/I conversion on the signal for which the recording level was adjusted and drives the head.
Feedback damping, which is used to suppress head resonance, is performed using EVR adjustment with Pin 26
(REC1CONT) and Pin 35 (REC2CONT).
Be careful to avoid capacitance coupling between the inputs and the outputs.
<Head amplifier>
This amplifies the playback signal from the head with low noise and high gain. Feedback damping circuit to
suppress head resonance is built in; the damping can be adjusted through external resistance connected to Pin
30 (PBDUMP1) and Pin 31 (PBDUMP2).
Be careful to avoid capacitance coupling between the playback system outputs and the head amplifier inputs.
<Middle-frequency tuner + SW>
This compensates for the frequency response of the playback signal. EVR adjustment of the center frequency
is performed with Pin 17 (MTF0); of Q with Pin 24 (MTQ), and of the CH1 and CH2 boost with Pin 13 (MTG1) and
Pin 15 (MTG2), respectively.
The CH1 and CH2 signals are switched according to the RFSWP timing and are output to MTOUT and
PCMOUT. The gain of the MTOUT signal is switched between 0 dB and 6 dB by Pin 3 (XGAIN).
<RFAGC>
This outputs the playback VIDEO signal at a fixed 380 mVp-p. The input has a built-in capacitor for DC cut-off
and external capacitor is not required.
The detector input includes an HPF with a cut-off frequency of approximately 1 MHz, so that the gain in the
bandwidth corresponding roughly to the Y signal is detected.
<Dropout detection>
A dropout is detected in the playback video signal, and a dropout pulse is output. The detection level is set to
the optimum level based on a 224 mVp-p input as a reference.
—20—
CXA1704R
<Control logic block>
In order to save power consumption, this IC is designed to reduce power supplied to those circuit blocks that
are not operating. Therefore, power saving operation is executed automatically when all of the power supplies are
turned on. In addition, this IC is equipped with many I/O switching circuits that must be switched with very
complex timing, so that internal logic is provided to control them.
The combinations of input and output in basic operations are as shown in the Control Logic Truth Table.
<Reference voltage in the IC>
Vreg (4.15 V) and Vg2 (2.45 V) are generated as the reference voltages used in the IC. Do not use these as
external power supplies because they could cause cross talk in the IC.
<EVR adjustment>
The voltage applied to the EVR adjustment pin is Vcc- variable, ranging from 1.8 V to Vcc.
—21—
CXA1704R
Recording Level Adjustment
YGCA gain control
LOWGCA (Video path) gain control
–10
gain (dB)
–20
–25
–15
–20
2
3
4
Pin 7 (YLEVEL) voltage (V)
5
–15
Pin 41 (VPSW1OUT)
Pin 38 (VPSW2OUT)
–10
YLEVEL=Vylev
→
–5
Pin 2 (AFMIN)
Pin 48 (ATFIN)
Pin 6 (YIN) →
Pin 41 (VPSW1OUT)
Pin 38 (VPSW2OUT) gain (dB)
0
–30
–35
2
–10
Pin 41 (VPSW1OUT)
gain (dB)
Pin 38 (VPSW2OUT)
–15
–20
Pin 4 (CIN)→
gain (dB)
–10
Pin 41 (VPSW1OUT)
Pin 38 (VPSW2OUT)
5
CGCA gain control
LOWGCA (PCM path) gain control
Pin 48 (ATFIN) →
3
4
Pin 5 (LOWLEVEL) voltage (V)
–25
When
YLEVEL=Vylev and
LOWLEV=Vllev
–15
–20
–25
–30
–30
2
–35
2
3
4
Pin 5 (LOWLEVEL) voltage (V)
5
—22—
3
4
Pin 1 (CCONT) voltage (V)
5
CXA1704R
Middle-frequency tuner fo control
Middle-frequency tuner Q control
15
6
5
4
Q
fo (MHz)
10
3
2
5
1
0
0
2
3
4
Pin 17 (MYF0) voltage (V)
5
2
Middle-frequency tuner boost control
20
15
Boost (dB)
10
5
0
2
3
4
Pins 13 and 15 (MTG1, MTG2) voltage (V)
5
—23—
3
4
Pin 24 (MTQ) voltage (V)
5
CXA1704R
Unit : mm
48PIN LQFP (PLASTIC)
9.0 ± 0.2
∗
7.0 ± 0.1
36
25
A
13
48
(0.22)
0.5 ± 0.2
(8.0)
24
37
12
1
+ 0.05
0.127 – 0.02
0.5 ± 0.08
+ 0.2
1.5 – 0.1
+ 0.08
0.18 – 0.03
0.1
0.1 ± 0.1
0° to 10°
0.5 ± 0.2
Package Outline
NOTE: Dimension “∗” does not include mold protrusion.
DETAIL A
PACKAGE STRUCTURE
PACKAGE MATERIAL
EPOXY / PHENOL RESIN
SOLDER PLATING
SONY CODE
LQFP-48P-L01
LEAD TREATMENT
EIAJ CODE
∗QFP048-P-0707-A
LEAD MATERIAL
42 ALLOY
PACKAGE WEIGHT
0.2g
JEDEC CODE
—24—