Rohm BA7780 Stereo zoom microphone amplifier for camcorder Datasheet

Video ICs
Stereo zoom microphone amplifier
for camcorders
BA7780KV
The BA7780KV is a microphone amplifier developed for use in camcorders. The IC features an electronic volume circuit for presetting the curve required for the stereo zoom function, a microphone element power supply regulator, a
wind-noise rejection filter, a current limiting circuit for external accessory power supplies, and an input for external
microphone input. The IC operates off a 3.3V power supply.
Applications
•Camcorders
•1)Features
Operates off a 3.0V to 5.25V power supply.
4) Adjustable microphone element sensitivity.
5) Matrix amplifier for stereo emphasis.
6) Automatic switching circuit for external inputs, and
built-in external monaural decision circuit.
2) Zoom microphone processing function on one chip.
3) Built-in electronic volume for external setting of sensitivity and control voltage.
•Absolute maximum ratings (Ta = 25°C)
Parameter
Symbol
Limits
Unit
VCC
7.0
V
mW
Power supply voltage
Pd
750∗
Operating temperature
Topr
– 10 ~ + 70
°C
Storage temperature
Tstg
– 55 ~ + 125
°C
Power dissipation
∗ Reduced by 7.5mW for each increase in Ta of 1°C over 25°C.
•Recommended operating conditions (Ta = 25°C)
Parameter
Power supply voltage
Symbol
Min.
Typ.
Max.
Unit
VCCS
3.0
—
5.25
V
1
Video ICs
BA7780KV
GND L 49
INV OUT L
GC OUT L
MTX IN L
MTX OUT L
BL OUT L
HPF IN L
BIAS L
EXTC L
45
OUT AMP IN L
VREG L
46
PRE OUT L
INT IN L
47
EXT IN L
SUB IN L
48
MODE 43
BG
•Block diagram
44
43
42
41
40
39
38
37
36
35
34
33
13dB
13dB
REC
EXT
GC
–
+
MIX1 IN L 50
32 OUT L
31 MIC MONO
INT: ON
INT
30 Z B
GZ CONT 51
SUB INV2 OUT 52
SUB INV2 IN 53
29 Z A
15dB
EXT
RFLT
–+
28 Z SENSE
SUB BUF2 OUT 54
5dB
BALANCE
INT
27 Z POINT
26 GAIN CONT
SUB VCA OUT 55
25 EX VCC OUT
SUB VCA IN 56
MIX
24 EX VCC
RFLT
SUB INV1 OUT 59
23 VCC
5dB
INT
BALANCE
22 Z AC
HPFC
SUB BUF2 IN 58
BIAS
MIX2 OUT 57
CImt
SUB BUF1 OUT 60
EXT
15dB
SUB BUF1 IN 61
MIX1 OUT 62
20 IN MONI
19 HPF CONT
MIX
INT
INT: 0N
MIX1 IN R 63
REG
13dB
GND R 64
2
21 Z BC
EXT
18 BIAS SUB
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
INT IN R
VREG R
EXT IN R
MODE 6
PRE OUT R
OUT AMP IN R
INV OUT R
GC OUT R
MTX IN R
MTX OUT R
BL OUT R
HPF IN R
BIAS R
EXTC R
17 OUT R
01
SUB IN R
+
–
RIPL
13dB
GC
Video ICs
BA7780KV
•Pin descriptions
Pin No.
Pin name
1
RIPL
2
Function
Pin voltage (V)
Format
For bias ripple filter capacitor
1.65
50kΩ
SUB IN R
Sub microphone input
1.65
100kΩ
3
INT IN R
Internal microphone input
1.65
75kΩ
4
VREG R
Regulator output
2.5
C
5
EXT IN R
External microphone input
1.65
75kΩ
Mode control 6 input
6
MODE 6
—
25kΩ
7
PRE OUT R
Preamplifier output
1.65
EF (P - P)
8
OUT AMP IN R
Out amplifier input
1.65
100kΩ
9
INV OUT R
Inverter output
1.65
EF (P - P)
10
GC OUT R
Gain control amplifier output
1.65
EF (P - P)
11
MTX IN R
Matrix amplifier input
1.65
B
12
MTX OUT R
Matrix amplifier output
1.65
EF (P - P)
13
BL OUT R
Zoom balance circuit output
1.65
EF (P - P)
14
HPF IN R
HPF input
1.65
100kΩ
15
BIAS R
Bias output
1.65
EF (P - P)
16
EXTC R
For connection of out amplifier output inhibit capacitor
2.3
C
17
OUT R
Signal output
1.65
C (P - P)
Sub bias output
18
BIAS SUB
19
HPF CONT
1.65
EF (P - P)
HFP control input
—
20
IN MONI
10kΩ
Input switch decision signal output
—
21
C
Z BC
For connection of noise cutting capacitor for zoom control signal
—
B
22
Z AC
For connection of noise cutting capacitor for zoom control signal
—
B
23
VCC
VCC
3.3
—
—
24
EX VCC
Current limiter VCC
4.75
25
EX VCC OUT
Current limiter output
4.5
C
26
GAIN CONT
Gain control amplifier switch input
—
50kΩ
27
Z POINT
Cross-point variation input for zoom balance circuit
—
B
28
Z SENSE
Sensitivity variation input for zoom balance circuit
—
B
29
Z A
Zoom control input
—
B
30
Z B
Zoom control input
—
B
31
MIC MONO
External microphone monaural decision signal output
—
C
EF (P - P)
32
OUT L
Signal output
1.65
33
EXTC L
For connection of out amplifier output inhibit capacitor
2.3
C
34
BIAS L
Bias output
1.65
EF (P - P)
35
HPF IN L
HPF input
1.65
100kΩ
36
BL OUT L
Zoom balance circuit output
1.65
EF (P - P)
37
MTX OUT L
Matrix amplifier output
1.65
EF (P - P)
38
MTX IN L
Matrix amplifier input
1.65
B
39
GC OUT L
Gain control amplifier output
1.65
EF (P - P)
40
INV OUT L
Inverter output
1.65
EF (P - P)
41
OUT AMP IN L
Out amplifier input
1.65
100kΩ
42
PRE OUT L
Preamplifier output
1.65
EF (P - P)
3
Video ICs
BA7780KV
Function
Pin voltage (V)
Format
—
25kΩ
External microphone input
1.65
75kΩ
VREG L
Regulator output
2.5
C
46
INT IN L
Internal microphone input
1.65
75kΩ
47
SUB IN L
Sub microphone input
1.65
100kΩ
48
BG
For regulator ripple filter capacitor
1.25
10kΩ
49
GND L
50
MIX 1 IN L
Pin No.
Pin name
43
MODE 43
Mode control 43 input
44
EXT IN L
45
Left channel GND
Mixer amplifier input
—
1.65
100kΩ
51
GZ CONT
Sub VCA control input
—
50kΩ
52
SUB INV2 OUT
Sub inverter 2 output
1.65
EF (P - P)
53
SUB INV2 IN
Sub inverter 2 input
1.65
B
54
SUB BUF2 OUT
Sub buffer 2 output
1.65
EF (P - P)
55
SUB VCA OUT
Sub VCA output
1.65
EF (P - P)
56
SUB VCA IN
Sub VCA input
1.65
100kΩ
57
MIX2 OUT
Mixer 2 output
1.65
EF (P - P)
58
SUB BUF2 IN
Sub buffer 2 input
1.65
100kΩ
59
SUB INV1 OUT
Sub inverter 1 output
1.65
EF (P - P)
60
SUB BUF1 OUT
Sub buffer 1 output
1.65
EF (P - P)
61
SUB BUF1 IN
Sub buffer 1 input
1.65
100kΩ
62
MIX1 OUT
Mixer 1 output
1.65
EF (P - P)
63
MIX1 IN R
Mixer 1 input
1.65
100kΩ
64
GND R
—
—
Right channel GND
∗ EF: emitter follower, P-P: push pull, B: base, and C: collector. All numerical values are standardized values.
4
—
Video ICs
BA7780KV
Electrical characteristics
•Measurement
conditions
Input signal level Int = – 31.5dBV
Ext = – 38.5dBV
Sub = – 33.5dBV (1kHz)
Monitoring pins: 17 and 32
∗ 1 JIS–A filter used
∗ 2 400Hz to 30kHz filter used
Unless otherwise noted, the following conditions apply:
Ta = 25°C, VCC3.3V, external supply voltage (pin 24) =
4.75V, pin 19 = “H” or open, pin 26 = 1 / 2VCC, pin 51 =
0.58 × pin 4, pin 27 = 0.733 × pin 4, pin 28 = 0.80 × pin 4,
pin 29 = 2.2V, pin 30 = 2.2V
Parameter
Symbol
Min.
Typ.
Max.
Unit
Conditions
IqE
—
8.5
12.0
mA
INT / EXT MIC IN, No input
Voltage gain 1
GVE
27.0
28.0
29.0
dB
EXT MIC IN
Voltage gain 2
GVIH
21.5
24.5
27.5
dB
INT MIC IN, GAIN CTL H
Voltage gain 3
GVIM
18.5
21.5
24.5
dB
INT MIC IN, GAIN CTL M
Voltage gain 4
GVIL
16.5
18.5
21.5
dB
INT MIC IN, GAIN CTL L
Distortion 1
THDW
—
0.05
0.5
%
INT MIC IN, WIDE, Vo = 300mVrms
Distortion 2
THDE
—
0.1
0.25
%
EXT MIC IN, VO = 300mVrms
Distortion 3
THDZ
—
0.15
0.5
%
Maximum output
VOM
0.75
0.95
—
Vrms
INT / EXT MIC IN, THD = 1%∗2
Output noise voltage 1 (EXT)
VONE
—
30
60
µVrms
EXT MIC IN, Rg = 1kΩ∗1
Output noise voltage 2 (INT, WIDE)
VONW
—
30
60
µVrms
Output noise voltage 3 (INT, ZOOM)
VONZ
—
60
120
µVrms
Input switch crosstalk (INT to EXT)
CTIE
—
– 76
– 70
dB
Current dissipation
INT MIC IN, ZOOM, V O = 300mVrms
INT MIC IN, Rg = 1kΩ∗1
GAIN CTL H
INT MIC IN, Rg = 1kΩ∗1
Pins 29 and 30 = 0V, GAIN CTL H
Note 1
Interchannel crosstalk
CTCH
—
– 76
– 70
dB
Note 2
GC OUT L / R gain differential
GVGLR
– 1.5
0.0
1.5
dB
INT MIC IN, HML, 10 39
Inverter OUT L / R gain differential
GVILR
– 1.5
0.0
1.5
dB
INT MIC IN, HML, 9 40
Internal microphone power supply output voltage
VREG
2.3
2.5
2.75
V
Pins 4 and 45 output current for 30kΩ load
External power supply output voltage
VEXT
4.3
4.5
—
V
Pin 25 DC for pin 25 output current of 25mA
ILTD
—
—
30
mA
VHSWH
1.6
—
VCC
V
“H” level, pin 6 / 43 DC
VHSWL
0
—
0.7
V
“L” level, pin 6 / 43 DC
VHGH
2.8
—
VCC
V
“H” level, pin 26 DC
VHGM
1.3
—
2.0
V
“M” level, pin 26 DC
VHGL
0
—
0.5
V
“L” level, pin 26 DC
VHHPFH
2.0
—
VCC
V
HPF OFF, 19pin DC
External power supply limit current
Input switching CTL holding voltage
Gain switching CTL holding voltage
HPF, CTL holding voltage
VHHPFL
MIX 1 gain
MIX 2 gain
0
GVM1-1
– 7.0
GVM1-2
– 1.0
GVM2-1
6.0
GVM2-2
– 1.0
Pin 25 output current when grounded
—
0.5
V
HPF ON, 19pin DC
– 6.0
– 5.0
dB
63→62 / 50→62 pin
0
1.0
dB
Gain differential for pins 63 to 62 and 50 to 62
7.0
8.0
dB
INT L / M / H, 2→57, 47→57pin
0
1.0
dB
Gain differential for pins 2 to 57 and 47 to 57
5
Video ICs
Parameter
BA7780KV
Symbol
Min.
Typ.
Max.
Conditions
Unit
12→13 or 37→36 pin
ZOOM - BALANCE
Gain 1
Rch / Lch
GV Z1-1 – 23.0 – 20.0 – 17.0
GV Z1-2 – 11.7
GV Z1-3
ZOOM - BALANCE
Gain 2
Rch / Lch
– 2.0
dB
29, 30 pin 0.0V (DC)
– 7.7
– 4.7
dB
29, 30 pin 0.8V (DC)
1.0
4.0
dB
29, 30 pin 2.2V (DC)
52→13 or 52→36 pin
GVZ2-1 – 23.0 – 20.0 – 17.0
GV Z2-2 – 11.7
GVZ2-3
– 2.0
dB
29, 30 pin 2.2V (DC)
– 7.7
– 4.7
dB
29, 30 pin 1.4V (DC)
1.0
4.0
dB
29, 30 pin 0.0V (DC)
28 pin 0.8 × 4pin, 29 30 pin 1.1V,
ZOOM - BALANCE
12→13 or 37→36 pin
Variable position
GV Z3–1
– 2.5
0.5
3.5
dB
27 pin 0.64 × 4pin (DC)
Rch / Lch
GV Z3–2
– 7.5
– 4.5
– 1.5
dB
27 pin 0.733 × 4pin (DC)
GV Z3–3 – 20.6 – 17.0 – 12.0
dB
27 pin 0.82 × 4pin (DC)
27 pin 0.733 × 4pin, 29 30 pin 0.4V,
ZOOM - BALANCE
12→13 or 37→36 pin
28 pin 0.59 × 4pin (DC)
Variable slope
GV Z4–1
– 5.5
– 2.5
0.5
Rch / Lch
GVZ4–2
– 9.5
– 6.5
– 3.5
dB
28 pin 0.69 × 4pin (DC)
GV Z4–3 – 17.5 – 14.5 – 11.5
dB
28 pin 0.8 × 4pin (DC)
Sub VCA gain
56pin
55pin
dB
GV VCA1
– 5.0
– 3.0
– 1.0
dB
51 pin 0.74 × 4pin (DC)
GV VCA2
– 2.0
0.0
2.0
dB
51 pin 0.58 × 4pin (DC)
GV VCA3
1.0
3.0
5.0
dB
51 pin 0.48 × 4pin (DC)
Note 1: Input switch crosstalk measurement method:
(pin 19 = “H” or open, pin 26 = GND, pin 27 = 0.733 × pin 4, pin 28 = 0.80 × pin 4, pin 29 = 2.2V, pin 30 = 2.2V)
Input 1kHz signals on the INT input pins (3 and 46) in INT input mode that give a distortion of 1% at the signal output pins (17 and 32), then
connect the EXT input pins (5 and 44) to GND via Rg = 1kΩ Switch to EXT input mode, and measure the relative output level of the output pins
(17 and 32).
Note 2: Interchannel crosstalk measurement method:
The mode pin conditions are the same as for input switch crosstalk.
Connect the input pin of the channel to be measured to GND via Rg = 1kΩ. Input a 1kHz signal on the other channel's input that gives a distortion
of 1% on the signal output pins (17 and 32), and measure the relative output level between the signal output pins (17 and 32).
6
01
13dB
02
03
04
REG
0.1
MODE6
07
0.1
08
09
10
GC
GC
39
38
37
0.1
10k 10k
11
12
INT: ON
13
0.1
1
2
SW2
14
EXT
INT
INT
15dB
5dB
35
EXT
36
15dB
5dB
INT: ON
+–
06
40
BIAS
05
13dB
BALANCE
BALANCE
EXT
INT
INT
41
13dB
42
15
34
CImt
33
16
HPFC
EXT MIC IN
+
64
RFLT
43
EXT
44
2200p
INT MIC IN
10k 3
2
32k 1
10
0.1
MIX
MIX
45
REG
RFLT
46
10k 10k
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
SUB BIAS
470p
63
62
61
60
59
58
0.1
0.1
0.1
57
56
55
54
+
–
0.1
10k
10k
53
52
51
0.1
13dB
47
30k
50
48
0.1
–+
0.1
0.1
49
0.1
0.1
SUB MIC IN
+
2
SW3
0.022
GND
10
1
0.1
GZ CONT
SUB MIC IN
INT MIC IN
EXT MIC IN
MODE43
Lch OUT
Rch OUT
HPF ON / OFF
IN MONI
Z BC
Z AC
VCC
EX VCC IN
EX VCC OUT
GAIN CONT
Z POINT
Z SENSE
Z A
Z B
MIC MONO
Video ICs
BA7780KV
•Measurement circuit
470p
2200p
0.022
30k
0.1
0.1
SW1
Units: R [Ω]
C [µF]
Fig. 1
7
Video ICs
BA7780KV
•Measurement circuit switching table (blank cells: no spesification)
SW1
Parameter
SW2
SW3
MODE6 MODE43 GAIN CTL
Signal input pin
H, L
M
—
L
L
M
Ext
H
—
H
Int
—
—
M
Int
—
—
L
Int
—
H
L
M
Int
—
L
L
—
Ext
—
H
L
M
Sub
—
H, L
L
L
Int, Ext, Sub
—
L
L
—
—
—
H
L
H
—
—
—
H
L
H
—
2
—
—
L
L
L
Int
INT
2
—
—
H
L
M
Int
EXT
2
—
—
L
L
—
Ext
GC out L / R gain differential
1
—
—
H
L
H, M, L
Int
Inverter OUT L / R gain differential
1
—
—
H
L
H, M, L
Int
Internal microphone power supply voltage
—
—
—
—
—
—
—
External power supply output voltage
—
—
—
—
—
—
—
External power supply limit current
—
—
—
—
—
—
—
2
—
—
H
Vth
—
Int, Ext
2
—
—
Vth
L
—
Int, Ext
2
—
—
H
L
Vth
Int
2
—
—
H
L
Vth
Int
—
Current dissipation
1
1
1
Voltage gain 1
—
—
—
Voltage gain 2
—
—
—
Voltage gain 3
—
—
—
Voltage gain 4
—
—
—
Distortion 1
2
—
Distortion 2
2
—
Distortion 3
1
—
Maximum output
1
—
Output noise voltage 1 (EXT)
2
—
Output noise voltage 2 (WIDE)
2
—
Output noise voltage 3 (ZOOM)
3
Input switch crosstalk (INT to EXT)
Interchannel crosstalk
Input switching CTL holding voltage
Gain switching CTL holding voltage
H, L
2
—
H
L
Vth
Int
HPF, CTL holding voltage
2
2.1
2.1
H
L
—
Int, Vth of pin 19
MIX 1 gain
—
—
—
H
L
M
Int
MIX 2 gain
—
—
—
H
L
—
Sub
ZOOM - BALANCE Gain 1
2
—
—
H
L
M
Int
ZOOM - BALANCE Gain 2
1
—
—
H
L
M
Sub
ZOOM - BALANCE Variable position
2
—
—
H
L
M
Int
ZOOM - BALANCE Variable inclination
2
—
—
H
L
M
Int
Sub VCA gain
—
—
—
H
L
—
Sub
∗ Gain CTL pin 26.
H, M, and L are VCC, 1/2VCC, and GND respectively.
Measure the voltage range that maintains the mode for Vth.
8
10k
05
06
EXT
0.1
08
13dB
07
09
10k
10
GC
0.1
3300
11
6800p
6800p
33k
EXT
INT
13
35
22k
22k
15
34
0.022
8200
14
EXT
INT
15dB
5dB
12
INT: 0N
36
15dB
5dB
37
INT: 0N
12k
10k
0.1
0.022
6800
04
3300
EXT MIC IN
0.1
2200
03
38
+–
2200
02
REG
INT
GC
39
0.022
INT MIC IN
01
13dB
MIX
BALANCE
BALANCE
40
BIAS
SUB MIC IN
64
63
62
41
13dB
42
CImt
33
16
HPFC
+
0.1
10k
0.1
61
60
RFLT
RFLT
43
8200
0.022
2200p
10
1k
1500
59
58
MIX
2700p
10k
0.01
10k
+
–
57
56
55
54
53
INT
EXT
44
33k
6800p
6800p
0.022
6800p
0.010
0.1
10k
10k
0.1
47k
52
0.1
51
REG
45
0.1
13dB
46
10k
50
47
10k
12k
3300
0.022
GND
3900p
10k
0.1
49
48
0.1
3300
–+
GZ CONT
+
0.022
6800
0.1
5600p
10
2200
2200
0.047
SUB MIC IN
INT MIC IN
EXT MIC IN
17
470p
HPF ON / OFF
Rch OUT
IN MONI
19
18
Z BC
22
20
VCC
Z AC
23
21
EX VCC OUT
EX VCC IN
24
GAIN CONT
26
25
Z SENSE
29
Z POINT
Z A
30
27
Z B
31
28
Lch OUT
MIC MONO
32
SUB BIAS
470p
Video ICs
BA7780KV
•Application example
2200p
0.022
0.1
0.047
0.1
Units: R [Ω]
C [µF]
Fig. 2
9
Video ICs
BA7780KV
Operation notes
•Points
to note regarding zoom operation
When using a microprocessor to vary the voltages on pins 29 and
30 after presetting the electronic volume sensitivity and control voltage range, and with the pin 27 and 28 voltage fixed at a certain
level, it is possible to minimize drift in the zoom characteristics due
to tempreature fluctuations and differences between individual ICs
by setting the pin 27 and 28 voltages using resistive voltage divider
circuits connected to the pin 4 regulator voltage output.
4
27
28
– 10
– 15
– 20
1.64V
1.84V
1.84V
1.94V
1.94V
2.04V
2.04V
12→13, 37→36pin
52→13, 52→36pin
0 0.1
0.6
1.1
1.6
2.1 2.2
29, 30pin CONTROL VOLTAGE: VCTL (V)
Fig. 4 Zoom control slope variation
characteristics
•External dimensions (Units: mm)
12.0 ± 0.3
10.0 ± 0.2
32
64
17
1.4 ± 0.1
1
0.10
33
49
0.5
16
0.125 ± 0.1
0.2 ± 0.1
0.10
VQFP64
10
0.5
12.0 ± 0.3
10.0 ± 0.2
48
–5
27pin
27pin
=
1.64V
Ta = 25°C
0
=
–5
28pin
=
28pin
17, 32pin OUTPUT ATTENUATION LEVEL: GVZ1 (dB)
Ta = 25°C
0
=
17, 32pin OUTPUT ATTENUATION LEVEL: GVZ1 (dB)
•Electrical characteristic curves
1.67V
1.67V
– 10
1.87V
1.87V
– 15
2.07V
1.67V
– 20
12→13, 37→36pin
52→13, 52→36pin
0 0.1
0.6
1.1
1.6
2.1 2.2
29, 30pin CONTROL VOLTAGE: VCTL (V)
Fig. 5 Zoom control position variation
characteristics
Fig. 3
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