Rohm BA7653AF Video signal switcher, 1 x 3-channel with clamped-input Datasheet

Multimedia ICs
Video signal switcher, 1 × 3-channel
with clamped-input
BA7653AF
The BA7653AF is a video-signal switching IC that contains a three-channel clamped-input multiplexer. The inputs
are sync-tip clamped (synchronous edge of the video input signals are aligned to the same voltage), and as the input
impedance is extremely large, it is possible to use a small value for the clamp capacitor (the recommended capacitor
is 0.01µF (FZ) ceramic).
Applications
•Video
cassette recorders, television and camcorders
•1)Features
Small clamp capacitors can be used (ceramic,
5) Wide dynamic range (3.1VP-P Typ. for VCC = 5V).
6) Excellent frequency characteristics (10MHz, 0dB
Typ.).
7) Low interchannel crosstalk ( – 70dB Typ.).
8) Voltage can be applied to the control pins even
when VCC is not applied.
3000pF (Min.), 0.01µF (FS) (recommended)).
2) Low supply voltage operation possible. Supply voltage range is 3.7V to 7.7V.
3) Superimposition used for fast switching speed with
low switching noise (70nsec. Typ.).
4) Low power consumption (when VCC = 5V, 25mW
Typ.).
•Absolute maximum ratings (Ta = 25°C)
Parameter
Symbol
Limits
Unit
Applied voltage
VCC
9
V
Power dissipation
Pd
500∗
mW
Operating temperature
Topr
– 25 ~ + 75
°C
Storage temperature
Tstg
– 55 ~ + 125
°C
∗ When mounted on a 50mm × 50mm board, reduced by 5mW for each increase in Ta of 1°C over 25°C.
•Recommended operating conditions (Ta = 25°C)
Parameter
Power supply voltage
Symbol
Limits
Unit
VCC
4.0 ~ 7.0
V
1
Multimedia ICs
BA7653AF
•Block diagram
IN1
1
8
GND
CTLa
2
7
OUT
IN2
3
6
VCC
5
IN3
Logic
CTLb
4
•Control pin truth table
•Pin descriptions
CTLa
CTLb
OUT
Input 1
L
L
IN1
Control input a
H
L
IN2
Input 2
L
H
IN3
Control input b
H
H
IN3
Pin No.
Pin name
1
IN1
Function
2
CTLa
3
IN2
4
CTLb
5
IN3
Input 3
6
VCC
Supply voltage
7
OUT
Output
8
GND
GND
•Electrical characteristics (unless otherwise noted, Ta = 25°C and V
Parameter
CC
= 5.0V)
Symbol
Min.
Typ.
Max.
Unit
Conditions
VCC
3.7
—
7.7
V
—
Supply current
ICC
2.7
5.0
8.2
mA
—
Maximum output level
Vom
2.6
3.1
—
VP-P
f = 1kHz, THD = 1.0%
Voltage gain
GV
– 0.5
0
0.5
dB
f = 1MHz, VIN = 1.0VP-P
Interchannel crosstalk
Cta
—
—
dB
f = 4.43MHz, VIN = 1.0VP-P
Gf
dB
f = 10MHz / 1MHz, VIN = 1.0VP-P
Operating voltage
Frequency characteristic
CTL switching voltage
– 70
– 3.0
0
1.0
VTH L
—
—
1.0
VTH H
2.5
—
—
VCC – CTL Threshold Level
VCC – VF
VTH =
× 20 (V)
45
V
•Guaranteed design parameters (unless otherwise noted, Ta = 25°C and V
CC
Parameter
2
Symbol
Min.
Differential gain
DG
Differential phase
DP
Unit
= 5.0V)
Conditions
Typ.
Max.
—
0
0.5
%
VIN = 1.0VP-P, standard staircase signal
—
0.5
1.0
deg
VIN = 1.0VP-P, standard staircase signal
Multimedia ICs
BA7653AF
•Input / output circuits
Pin No.
Pin name
DC voltage
(VCC = 5V)
Input / output
impedance
Equivalent circuit
VCC
1
IN 1
1.65V
10MΩ
or more
IN1
100
50µA
VCC
2.3V
2
CTLa
—
—
50k
CTLa
1.9V
VCC
3
IN 2
1.65V
10MΩ
or more
IN2
100
50µA
VCC
2.3V
4
CTLb
—
—
50µA
50k
CTLb
1.9V
3
Multimedia ICs
Pin No.
Pin name
BA7653AF
DC voltage
(VCC = 5V)
Input / output
impedance
Equivalent circuit
VCC
5
IN 3
1.65V
10MΩ
or more
IN3
100
50µA
VCC
6
VCC
5.0V
—
VCC
7
OUT
0.95V
OUT
26Ω
1mA
VCC
8
GND
0V
—
GND
4
Multimedia ICs
BA7653AF
•Application examples
GND
IN1
C. Video In
1
8
2
7
0.01µ
OUT
CTLa
Logic
C. Video Out
VCC
VCC
IN2
C. Video In
3
6
+
0.01µ
47µ
CTLb
Logic
4
Logic
0.1µ
IN3
5
C. Video In
0.01µ
When superimposition is used
GND
IN1
C. Video In
1
8
2
7
0.01µ
Logic
C. Video or DC Out
OUT
CTLa
VCC
VCC
IN2
3
6
+
DC1.7V or more
47µ
Logic
CTLb
4
Logic
0.1µ
IN3
5
DC1.7V or more
Fig. 1
•
Operation notes
(1) To ensure stable clamp operation, the output
impedance of the previous stage connected to the
inputs should be 1kΩ or lower.
(2) If large input clamp capacitors are used, the time
constant of the circuit will mean that some time will be
required until stable operation after power is applied.
The value for the input clamp capacitors is 0.1µF Max.
(0.01µF (FZ) ceramic capacitor recommended).
(3) The BA7653AF is a three-channel multiplexer, but
two-channel operation is also possible. In this case, if
the unused input is left open it will oscillate, but this will
not effect the other inputs and cause problems. If this is
a concern, ground the unused input via a capacitor, or
connect it directly to VCC.
(4) If control inputs are left open they will be unstable,
set to H or L.
(5) When using superimposition, the DC voltage directly applied to the inputs should be at least 1.7V.
5
Multimedia ICs
BA7653AF
•External dimensions (Units: mm)
1
4
0.11
1.27
0.15 ± 0.1
4.4 ± 0.2
5
1.5 ± 0.1
6.2 ± 0.3
5.0 ± 0.2
8
0.4 ± 0.1
0.3Min.
0.15
SOP8
6
Similar pages