5

Multimedia ICs

BA7653AF

1

2

3

4

8

7

6

5

IN1

CTLa

IN2

CTLb

GND

OUT

IN3

Logic

Logic

Logic

C. Video In

C. Video In

C. Video In

C. Video Out

0.01

µ

0.01

µ

0.01

µ

47

µ

0.1

µ

+

When superimposition is used

1

2

3

4

8

7

6

5

IN1

CTLa

IN2

CTLb

GND

OUT

IN3

Logic

Logic

Logic

47

µ

0.1

µ

DC1.7V or more

DC1.7V or more

C. Video or DC Out

C. Video In

0.01

µ

Fig. 1

+

(1) To ensure stable clamp operation, the output

impedance of the previous stage connected to the

inputs should be 1k

Ω 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 0.1

µF Max.

(0.01

µF (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

(4) If control inputs are left open they will be unstable,

set to H or L.

(5) When using superimposition, the DC voltage direct-

ly applied to the inputs should be at least 1.7V.