Multimedia ICs
Input selector switch for high
definition displays
BA7657F / BA7657S
The BA7657F and BA7657S are for high definition displays, and have internal switches for switching between broadband RGB signals and HD / VD signals, as well as an internal synchronization separator. These ICs simplify the designing of input units for deluxe displays.
•ApplicationsHDTV, video board for personal computer, etc.
CRT display,
•Features on a single 5V power supply.
1) Operates
3) Internal HD / VD switch.
4) Internal synchronization separator for synchronizing
signals superimposed onto G signals.
2) Internal broadband RGB switch (frequency characteristics: 230MHz, – 3dB).
•Absolute maximum ratings (Ta = 25°C)
Parameter
Symbol
Limits
Unit
VCC
8.0
V
Power supply voltage
Power
dissipation
BA7657F
550∗
Pd
1200∗
mW
Operating temperature
Topr
– 25 ~ + 75
°C
Storage temperature
Tstg
– 55 ~ + 125
°C
BA7657S
∗ Reduced by 5.5mW (BA7657F) or 12mW (BA7657S) 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
VCC
4.5
5.0
5.5
V
1
Multimedia ICs
BA7657F / BA7657S
•Pin descriptions
Pin No.
Pin name
1
Red 1 input
Function
Pin No.
Pin name
Function
2
Color signal R1 input
14
VD output
Vertical synchronization signal VD output
HD Sync signal Detecting phase of the synchronization
detector
signal detector circuit
15
Blue output
Color signal B output
16
Control
Control (high = IN1, low = IN2)
17
Composite sync
output
Synchronization signal output
18
Composite video Composite signal input
input
(Sync on Green)
3
Green 1 input
4
Ground
5
Blue 1 input
6
Ground
7
Red 2 input
8
Ground
9
Green 2 input
10
Ground
Color signal G1 input
Ground
Color signal B1 input
Ground
19
11
Blue 2 input
12
VD 1 input
Vertical synchronization signal VD1 input
13
VD 2 input
HD output
Horizontal synch. signal HD output
HD 2 input
Horizontal synch. signal HD2 input
24
Color signal B2 input
Color signal R output
23
Ground
Red output
22
Color signal G2 input
VCC
21
Ground
Green output
20
Color signal R2 input
Color signal G output
HD 1 input
Horizontal synch. signal HD1 input
Power supply
Vertical synchronization signal VD2 input
•Output selection setting table
CTL
R
G
B
HD
VD
H
IN1
IN1
IN1
IN1
IN1
L
IN2
IN2
IN2
IN2
IN2
•Input / output circuits
R. G. B input
HD. VD input
R. G. B output
VCC
VCC
VCC
50
35k
6.8k
1, 3, 5
7, 9, 11pin
12, 13
23, 24pin
100
15, 19, 21pin
21k
1k
400
1k
50k
15k
5mA
3
