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ROHM Semiconductor |
Multimedia ICs
Video signal switcher
BA7645N
The BA7645N is a four-channel analog multiplexer with mute, designed for use in video cassette recorders. It fea-
tures a large dynamic range, and wide operating frequency range, and has sync-tip inputs which are ideal for switch-
ing video signals.
•Applications
Video cassette recorders and televisions
•Features
1) 4-input / 1-output switches.
2) Built-in mute.
3) Sync-tip inputs.
4) Wide operating supply voltage range
(4.5V to 13.0V).
5) Low power consumption (48mW Typ.).
6) Excellent frequency characteristics
(10MHz, 0dB Typ.).
7) Wide dynamic range (3.5VP-P Typ.).
8) Low interchannel crosstalk
( – 65dB Typ., f = 4.43MHz).
•Absolute maximum ratings (Ta = 25°C)
Parameter
Symbol
Power supply voltage
VCC
Power dissipation
Pd
Operating temperature
Topr
Storage temperature
Tstg
∗ Reduced by 8.5mW for each increase in Ta of 1°C over 25°C.
Limit
13.5
850∗
– 25 ~ + 75
– 55 ~ + 125
Unit
V
mW
°C
°C
•Block diagram
MUTE
LOGIC
1 2 3 4 5 6 7 8 9 10
•Truth table
CTLA
CTLB
L (OPEN) L (OPEN)
L (OPEN)
H
H L (OPEN)
HH
∗∗
∗ Either "L (open)" or "H".
CTLC
L (OPEN)
L (OPEN)
L (OPEN)
L (OPEN)
H
OUT
IN1
IN2
IN3
IN4
MUTE
1
Multimedia ICs
•Equivalent circuits
CLAMP INPUT
Input bias current 1µA [Typ.]∗
Input clamp voltage 2.1V [VCC = 5V,Typ.]∗
BA7645N
∗ Reference value
D1
D2
Vcc
Q1 R2
100
Q2
0.8µA
100µA
OUTPUT
Vcc
Q1 D1
2mA
D2
OUT
Output impedance 20Ω [Typ.]∗
Output DC voltage 0.55V [VCC = 5V, Typ.]∗
CTLA / CTLB
Vcc
R4 20k
CTLA / B
D2
R1 R2
100 50k
Q3
R3 34k
CTLC
Vcc
R4 30k
CTLC
D2
R1 R2
100 45k
Q3
R3 29k
•Electrical characteristics (unless otherwise noted Ta = 25°C and VCC = 5V)
Parameter
Symbol Min. Typ. Max. Unit
Conditions
Operating voltage
Supply current
Maximum output level
Voltage gain
Interchannel crosstalk
VCC 4.5
ICC —
Vom 3.0
GV – 0.5
CT —
Frequency characteristics Cf
CTL pin switching level A VTH-A
CTL pin switching level B VTH-B
CTL pin switching level C VTH-C
᭺Not designed for radiation resistance.
– 3.0
1.0
1.0
1.0
—
9.5
3.5
0
– 65
13.0
14.5
—
+ 0.5
—
0 + 1.0
2.0 3.0
2.0 3.0
2.0 3.0
V—
mA —
VP-P f = 1kHz, THD = 0.5%
dB f = 1MHz, VIN = 1.0VP-P
dB
f = 4.43MHz,
VIN = 1.0VP-P
dB f = 10MHz / 1MHz,
VIN = 1.0VP-P
V—
V—
V—
2
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