Datasheet BA7780KV Datasheet (ROHM)

1

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

•

Features

1) Operates off a 3.0V to 5.25V power supply.

2) Zoom microphone processing function on one chip.

3) Built-in electronic volume for external setting of sen­sitivity and control voltage.

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.

•

Absolute maximum ratings (Ta = 25°C)

•

Recommended operating conditions (Ta = 25°C)

Parameter

Symbol Limits Unit

V

CC

7.0 V

Pd 750

∗

mW

Topr

°C

Tstg °C

– 10 ~ + 70

– 55 ~ + 125

Power supply voltage
Power dissipation
Operating temperature
Storage temperature

∗

Reduced by 7.5mW for each increase in Ta of 1°C over 25°C.

Parameter Symbol Min. Typ. Max. Unit

V

CCS 3.0 — 5.25 V

Power supply voltage

2

Video ICs BA7780KV

•

Block diagram

01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16

32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17

48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64

MIX

REC

EXT

INT

13dB

GC

–
+

15dB

5dB

EXT

INT

BALANCE

RFLT

EXT

INT

13dB

RFLT

MIX

13dB

BALANCE

INT: 0N

GC

15dB

5dB

EXT

INT

BIAS

HPFC

CImt

13dB

OUT L

MIC MONO

Z B

Z A
Z SENSE
Z POINT
GAIN CONT

EX V

CC OUT

EX V

CC

VCC

Z AC

Z BC
IN MONI
HPF CONT
BIAS SUB

OUT R

BG

SUB IN L

INT IN L

VREG L

EXT IN L

MODE 43

PRE OUT L

OUT AMP IN L

INV OUT L

GC OUT L

MTX IN L

MTX OUT L

BL OUT L

HPF IN L

BIAS L

EXTC L

RIPL

SUB IN R

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

GND L

MIX1 IN L

GZ CONT

SUB INV2 OUT

SUB INV2 IN

SUB BUF2 OUT

SUB VCA OUT

SUB VCA IN

MIX2 OUT

SUB BUF2 IN

SUB INV1 OUT

SUB BUF1 OUT

SUB BUF1 IN

MIX1 OUT

MIX1 IN R

GND R

INT: ON

REG

–

+

+–

3

Video ICs BA7780KV

•

Pin descriptions

1 RIPL 1.65 50kΩ
2 1.65 100kΩ
3 1.65 75kΩ
4 2.5 C
5 1.65 75kΩ
6 — 25kΩ
7 1.65 EF (P - P)
8 1.65 100kΩ

9 1.65 EF (P - P)
10 1.65 EF (P - P)
11 1.65 B
12 1.65 EF (P - P)
13 1.65 EF (P - P)
14 1.65 100kΩ
15 1.65 EF (P - P)
16 2.3 C
17 1.65 C (P - P)
18 1.65 EF (P - P)
19 — 10kΩ
20 —C
21 —B
22 —B
23 VCC 3.3 —
24 4.75 —
25 4.5 C
26 — 50kΩ
27 —B
28 —B
29 —B
30 —B
31 —C
32 1.65 EF (P - P)
33 2.3 C
34 1.65 EF (P - P)
35 1.65 100kΩ
36 1.65 EF (P - P)
37 1.65 EF (P - P)
38 1.65 B
39 1.65 EF (P - P)
40 1.65 EF (P - P)
41 1.65 100kΩ
42 1.65 EF (P - P)

SUB IN R

INT IN R

VREG R

EXT IN R

MODE 6

OUT AMP IN R

PRE OUT R

INV OUT R
GC OUT R

MTX IN R

MTX OUT R

BL OUT R

HPF IN R

BIAS R

EXTC R

OUT R

BIAS SUB

HPF CONT

IN MONI

Z BC
Z AC

EX V

CC

EX VCC OUT

GAIN CONT

Z POINT

Z SENSE

Z A
Z B

MIC MONO

OUT L

EXTC L

BIAS L

HPF IN L

BL OUT L

MTX OUT L

MTX IN L

GC OUT L

INV OUT L

OUT AMP IN L

PRE OUT L

Pin No.

For bias ripple filter capacitor
Sub microphone input
Internal microphone input
Regulator output
External microphone input
Mode control 6 input
Preamplifier output
Out amplifier input
Inverter output
Gain control amplifier output
Matrix amplifier input
Matrix amplifier output
Zoom balance circuit output
HPF input
Bias output
For connection of out amplifier output inhibit capacitor
Signal output
Sub bias output
HFP control input
Input switch decision signal output
For connection of noise cutting capacitor for zoom control signal
For connection of noise cutting capacitor for zoom control signal
V

CC

Current limiter VCC
Current limiter output
Gain control amplifier switch input
Cross-point variation input for zoom balance circuit
Sensitivity variation input for zoom balance circuit
Zoom control input
Zoom control input
External microphone monaural decision signal output
Signal output
For connection of out amplifier output inhibit capacitor
Bias output
HPF input
Zoom balance circuit output
Matrix amplifier output
Matrix amplifier input
Gain control amplifier output
Inverter output
Out amplifier input
Preamplifier output

Pin voltage (V)

FormatFunction

Pin name

4

Video ICs BA7780KV

Pin No.

43 MODE 43 — 25kΩ
44 EXT IN L 1.65 75kΩ
45 VREG L 2.5 C
46 INT IN L 1.65 75kΩ
47 SUB IN L 1.65 100kΩ
48 BG 1.25 10kΩ
49 GND L ——
50 MIX 1 IN L 1.65 100kΩ
51 GZ CONT — 50kΩ
52 SUB INV2 OUT 1.65 EF (P - P)
53 SUB INV2 IN 1.65 B
54 SUB BUF2 OUT 1.65 EF (P - P)
55 SUB VCA OUT 1.65 EF (P - P)
56 SUB VCA IN 1.65 100kΩ
57 MIX2 OUT 1.65 EF (P - P)
58 SUB BUF2 IN 1.65 100kΩ
59 SUB INV1 OUT 1.65 EF (P - P)
60 SUB BUF1 OUT 1.65 EF (P - P)
61 SUB BUF1 IN 1.65 100kΩ
62 MIX1 OUT 1.65 EF (P - P)
63 MIX1 IN R 1.65 100kΩ
64 GND R ——

Pin voltage (V)

FormatFunction

Pin name

Mode control 43 input
External microphone input
Regulator output
Internal microphone input
Sub microphone input
For regulator ripple filter capacitor
Left channel GND
Mixer amplifier input
Sub VCA control input
Sub inverter 2 output
Sub inverter 2 input
Sub buffer 2 output
Sub VCA output
Sub VCA input
Mixer 2 output
Sub buffer 2 input
Sub inverter 1 output
Sub buffer 1 output
Sub buffer 1 input
Mixer 1 output
Mixer 1 input
Right channel GND

∗

EF: emitter follower, P-P: push pull, B: base, and C: collector. All numerical values are standardized values.

5

Video ICs BA7780KV

Parameter

Symbol Min. Typ. Max. Unit

Conditions

I

qE — 8.5 12.0 mA

GV

E 27.0 28.0 29.0 dB

GV

IH 21.5 24.5 27.5 dB

GV

IM 18.5 21.5 24.5 dB

GV

IL 16.5 18.5 21.5 dB

THD

W — 0.05 0.5 %

THD

E — 0.1 0.25 %

THD

Z — 0.15 0.5 %

V

OM 0.75 0.95 — Vrms

VONE —3060µVrms
VONW —3060µVrms

VONZ — 60 120µVrms

CTIE — – 76 – 70 dB

CT

CH — – 76 – 70 dB

GV

GLR – 1.5 0.0 1.5 dB

10 39

GVILR – 1.5 0.0 1.5 dB

940

VREG 2.3 2.5 2.75 V

V

EXT 4.3 4.5 — V

I

LTD — — 30 mA

V

HSWH 1.6 — V

V

HSWL 0—0.7V

V

HGH 2.8 — V

V

HGM 1.3 — 2.0 V

V

HGL 0—0.5V

V

HHPFH 2.0 — V

V

HHPFL 0—0.5V

GV

M1-1 – 7.0 – 6.0 – 5.0 dB

GV

M1-2 – 1.0 0 1.0 dB

GV

M2-1 6.0 7.0 8.0 dB

GV

M2-2 – 1.0 0 1.0 dB

EXT MIC IN, VO = 300mVrms

Note 1
Note 2

V

CC

V

CC

V

CC

GAIN CTL H

INT MIC IN, ZOOM, V

O

= 300mVrms

INT MIC IN, WIDE, Vo = 300mVrms

INT MIC IN, GAIN CTL L

INT MIC IN, GAIN CTL M

INT MIC IN, GAIN CTL H

EXT MIC IN

INT / EXT MIC IN, No input

Pins 29 and 30 = 0V, GAIN CTL H

INT MIC IN, HML,
INT MIC IN, HML,

HPF OFF, 19pin DC
HPF ON, 19pin DC
63→62 / 50→62 pin

INT L / M / H, 2→57, 47→57pin

INT / EXT MIC IN, THD = 1%

∗

2

EXT MIC IN, R

g = 1k

Ω

∗

1

INT MIC IN, R

g = 1k

Ω

∗

1

INT MIC IN, R

g = 1k

Ω

∗

1

Current dissipation
Voltage gain 1
Voltage gain 2
Voltage gain 3
Voltage gain 4
Distortion 1
Distortion 2
Distortion 3
Maximum output
Output noise voltage 1 (EXT)

Output noise voltage 2 (INT, WIDE)

Output noise voltage 3 (INT, ZOOM)

Input switch crosstalk (INT to EXT)
Interchannel crosstalk

GC OUT L / R gain differential
Inverter OUT L / R gain differential

Internal microphone power supply output voltage
External power supply output voltage
External power supply limit current

Input switching CTL holding voltage

Gain switching CTL holding voltage

HPF, CTL holding voltage

MIX 1 gain

MIX 2 gain

Pins 4 and 45 output current for 30kΩ load
Pin 25 DC for pin 25 output current of 25mA
Pin 25 output current when grounded
“H” level, pin 6 / 43 DC
“L” level, pin 6 / 43 DC
“H” level, pin 26 DC
“M” level, pin 26 DC
“L” level, pin 26 DC

Gain differential for pins 63 to 62 and 50 to 62

Gain differential for pins 2 to 57 and 47 to 57

•

Electrical characteristics
Measurement conditions
Unless otherwise noted, the following conditions apply:
Ta = 25°C, V

CC3.3V, external supply voltage (pin 24) =

4.75V, pin 19 = “H” or open, pin 26 = 1 / 2V

CC, 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

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

6

Video ICs BA7780KV

GV

Z1-1

– 23.0 – 20.0 – 17.0 dB 29, 30 pin 0.0V (DC)

GV

Z1-2

– 11.7 – 7.7 – 4.7 dB 29, 30 pin 0.8V (DC)

GV

Z1-3

– 2.0 1.0 4.0 dB 29, 30 pin 2.2V (DC)

GV

Z2-1

– 23.0 – 20.0 – 17.0 dB 29, 30 pin 2.2V (DC)

GV

Z2-2

– 11.7 – 7.7 – 4.7 dB 29, 30 pin 1.4V (DC)

GV

Z2-3

– 2.0 1.0 4.0 dB 29, 30 pin 0.0V (DC)

Parameter

Symbol Unit

Conditions

Min. Typ. Max.

GV

Z3–1

– 2.5 0.5 3.5 dB 27 pin 0.64

× 4pin (DC)

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)

GV

Z4–1

– 5.5 – 2.5 0.5 dB 28 pin 0.59

× 4pin (DC)

GV

Z4–2

– 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)

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)

12

→13 or 37→36 pin

52→13 or 52→36 pin

28 pin 0.8 × 4pin, 29 30 pin 1.1V,
12→13 or 37→36 pin

27 pin 0.733 × 4pin, 29 30 pin 0.4V,
12→13 or 37→36 pin

Sub VCA gain

Variable slope

Variable position

Gain 2

Gain 1
Rch / Lch

Rch / Lch

Rch / Lch

Rch / Lch

56pin 55pin

ZOOM - BALANCE

ZOOM - BALANCE

ZOOM - BALANCE

ZOOM - BALANCE

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 R

g = 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 R

g = 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).

7

Video ICs BA7780KV

01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16

323130292827262524232221201918

17

48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33

495051525354555657585960616263

64

MIX

EXT

INT

13dB

GC

15dB

5dB

EXT

INT

BALANCE

EXT

INT

13dB

MIX

13dB

BALANCE

GC

15dB

5dB

EXT

INT

BIAS

CImt

13dB

MIC MONO

Z B

Z A

V

CC

Z AC

Z BC

IN MONI

SUB BIAS

10k

10k

0.1

0.1

0.1

0.1

30k

0.1

0.1

2200p

0.022

1

2

10

+

0.1

0.1

10k

10k

10k

32k

1

2

3

SW1

0.1

0.1

0.1

0.1

470p

SW3

10k

10k

0.1

0.1

0.1

0.1

30k

0.1

0.1

2200p

0.022

1

2

10

+

470p

MODE6

SW2

MODE43

GND

Z SENSE

Z POINT

GAIN CONT

EX V

CC

OUT

EX V

CC

IN

INT: ON

INT: ON

SUB MIC IN

INT MIC IN

EXT MIC IN

EXT MIC IN

INT MIC IN

SUB MIC IN

RFLT

RFLT

GZ

CONT

REG

REG

Lch OUT

Rch OUT

HPF ON / OFF

Units:

HPFC

R [Ω]
C [µF]

Fig. 1

–+

–+

+

–

•

Measurement circuit

8

Video ICs BA7780KV

SW1 SW2 SW3 MODE6 MODE43 GAIN CTL

1
—
—
—
—

—
—
—

—
—

—

—
—
—
—
—
—
—
—
—
—
—

—

—
—
—
—
—
—
—
—
—
—
—
—

—
—
—
—
—
—
—

—
—
—
—
—
—
—
—
—
—
—

—

—
—
—
—
—
—
—
—
—
—
—
—

—
—
—
—
—
—
—

—
—

—
—
—

—
—

—
—
—

1 1 H, L H, L M

LL—M Ext

—

—
—
—

—
—
—

H H Int

M Int

L Int

2HLM

—

—

—

—
—
—
—
—

—

—

—

Int
2 L L Ext
1 H L M Sub
1 H, L L L Int, Ext, Sub
2LL
2HLH
3HLH

2 L L L Int

INT 2 H L M Int

EXT 2 L L Ext

1 H L H, M, L Int
1 H L H, M, L Int

2 H Vth Int, Ext
2 Vth L Int, Ext
2 H L Vth Int
2 H L Vth Int
2 H L Vth Int
2 2.1 2.1 H L

H L M Int

H L Sub
2 H L M Int
1 H L M Sub
2 H L M Int
2 H L M Int

H L Sub

Int, Vth of pin 19

Signal input pin

Parameter
Current dissipation
Voltage gain 1
Voltage gain 2
Voltage gain 3
Voltage gain 4
Distortion 1
Distortion 2
Distortion 3
Maximum output
Output noise voltage 1 (EXT)
Output noise voltage 2 (WIDE)
Output noise voltage 3 (ZOOM)

Input switch crosstalk (INT to EXT)

Interchannel crosstalk

GC out L / R gain differential
Inverter OUT L / R gain differential
Internal microphone power supply voltage
External power supply output voltage
External power supply limit current

Input switching CTL holding voltage

Gain switching CTL holding voltage

HPF, CTL holding voltage
MIX 1 gain
MIX 2 gain
ZOOM - BALANCE Gain 1
ZOOM - BALANCE Gain 2
ZOOM - BALANCE Variable position
ZOOM - BALANCE Variable inclination
Sub VCA gain

∗

Gain CTL pin 26.
H, M, and L are V

CC, 1/2VCC, and GND respectively.

Measure the voltage range that maintains the mode for Vth.

•

Measurement circuit switching table (blank cells: no spesification)

9

Video ICs BA7780KV

01 02 03 04 05 06 07 08

09 10

11 12 13 14 15 16

32

313029

28

272625

242322

2120191817

48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33

49

505152

53

545556

575859

6061626364

MIX

EXT

INT

13dB

GC

15dB

5dB

EXT

INT

BALANCE

RFLT

EXT

INT

13dB

RFLT

MIX

13dB

BALANCE

INT: 0N

GC

15dB

5dB

EXT

INT

BIAS

CImt

INT: 0N

13dB

MIC MONO

Z B

Z A

V

CC

Z AC

Z BC

IN MONI

SUB BIAS

10k

0.1

0.1

0.1

0.1

0.1

0.022

10

+

0.1

0.1

10k

10k

10k

0.1

0.1

0.1

470p

0.1

0.1

0.1

0.1

10

+

0.022

2200

6800

2200

0.022

2200

6800

2200

33k

3300

12k

6800p

6800p

0.047

3300

10k

2200p

22k

0.022

0.022

8200

10k

0.1

0.022

470p

33k

3300

12k

6800p

6800p

0.047

3300

10k

2200p

22k

0.022

0.022

8200

5600p

10k

GND

10k

0.010

0.01

1k

1500

10k

2700p

10k

EXT MIC IN

INT MIC IN

SUB MIC IN

SUB MIC IN

INT MIC IN

EXT MIC IN

6800p

3900p

47k

Z SENSE

Z POINT

GAIN CONT

EX V

CC OUT

EX V

CC IN

GZ CONT

HPF ON / OFF

REG

Lch OUT

Rch OUT

HPFC

REG

Units: R [Ω]

C [µF]

Fig. 2

–+

–+

+
–

•

Application example

•

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.

10

Video ICs BA7780KV

•

Electrical characteristic curves

17, 32pin OUTPUT ATTENUATION LEVEL: GVZ1 (dB)

29, 30pin CONTROL VOLTAGE: VCTL (V)

– 20

0.1

– 15

– 10

– 5

0

0.6 1.1 1.6 2.1

28pin

=

1.64V

1.84V

1.94V

2.04V

28pin

=

1.64V

1.84V

1.94V

2.04V

Ta = 25°C

12→13, 37→36pin
52→13, 52→36pin

0 2.2

Fig. 4 Zoom control slope variation

characteristics

4

27

28

Fig. 3

17, 32pin OUTPUT ATTENUATION LEVEL: GVZ1 (dB)

29, 30pin CONTROL VOLTAGE: VCTL (V)

– 20

0.1

– 15

– 10

– 5

0

0.6 1.1 1.6 2.1

27pin

=

1.67V

1.87V

1.67V

Ta = 25°C

12→13, 37→36pin
52→13, 52→36pin

2.07V

1.87V

27pin

=

1.67V

0 2.2

Fig. 5 Zoom control position variation

characteristics

•

External dimensions (Units: mm)

VQFP64

48

33

32

17

16

1

49

64

10.0 ± 0.2

12.0 ± 0.3

10.0 ± 0.2

12.0 ± 0.3

0.2 ± 0.1

0.5

0.125 ± 0.1

0.5

0.10

1.4 ± 0.1

0.10