INTEGRATED CIRCUITS
DATA SHEET
TDA8440
Switch for CTV receivers
Product specification
File under Integrated Circuits, IC02
November 1985
Philips Semiconductors
Product specification
Switch for CTV receivers
TDA8440
GENERAL DESCRIPTION
The TDA8440 is a versatile video/audio switch, intended to
be used in CTV receivers equipped with an AUXILIARY
VIDEO/AUDIO plug.
It provides two 3-state switches for audio channels and
one 3-state switch for the video channel and a video
amplifier with selectable gain (times 1 or times 2).
The integrated circuit can be used in conjunction with a
microcontroller from the MAB8400 family, and is controlled
via a bidirectional I
2
C bus. Sufficient sub-addressing is
provided for the I
2
C bus mode. It can also be controlled
directly by d.c. switching signals.
Features
•
Combined analogue and digital circuitry gives maximum
flexibility in channel switching
•
3-state switches for all channels
•
Selectable gain for the video channels
•
Sub-addressing facility
•
I
2
C bus or non-I
2
C bus mode (controlled by d.c.
voltages)
•
Slave receiver in the I
2
C bus mode
•
External OFF command
•
System expansion possible up to 7 devices (14 sources)
•
Static short-circuit proof outputs
QUICK REFERENCE DATA
Supply voltage range
Supply current (without load)
Storage temperature
Operating ambient temperature range
PACKAGE OUTLINE
18-lead DIL; plastic (SOT102); SOT102-1; 1996 November 19.
V
15-4
I
15
T
stg
T
amb
10 to 13,2 V
typ.
max.
max.
33 mA
50 mA
+
125
°C
0 to
+
70
°C
November 1985
2
Philips Semiconductors
Product specification
Switch for CTV receivers
TDA8440
S0, S1, S2 and OFF (pins 11, 13, 6 and 2) connected to V
P
or GND.
If more than 1 device is used, then the outputs and the pins 8 (bias decoupling of the audio inputs) may be connected in parallel.
Fig.1 Block diagram and test circuit.
November 1985
3
Philips Semiconductors
Product specification
Switch for CTV receivers
FUNCTIONAL DESCRIPTION
TDA8440
The TDA8440 is a monolithic system of switches and can be used in CTV receivers equipped with an AUXILIARY
VIDEO/AUDIO plug.
The IC incorporates 3-state switches; they comprise:
a) An electronic video switch with selectable gain (times 1 or times 2) for switching between an internal video signal
(from the IF amplifier) and an AUXILIARY input signal.
b) Two electronic audio switches, for two sound channels (stereo or dual language), for switching between internal
audio sources and signals from the AUXILIARY VIDEO/AUDIO plug.
A selection can be made between two input signals and an OFF-state. The OFF-state is necessary if more than one
TDA8440 device is used.
The SDA and SCL pins can be connected to the I
2
C bus or to d.c. switching voltages. Inputs S
0
(pin 11), S
1
(pin 13), and
S
2
(pin 6) are used for selection of sub-addresses or switching to the non-I
2
C mode. Inputs S
0
, S
1
and S
2
can be
connected to the supply voltage (H) or to ground (L). In this way no peripheral components are required for selection.
Table 1
Sub-addressing
SUB-ADDRESS
S
2
L
L
L
L
H
H
H
H
NON-I
2
C BUS CONTROL
If the TDA8440 switching device has to be operated via the AUXILIARY VIDEO/AUDIO plug, inputs S
2
, S
1
and S
0
must
be connected to the supply line (12 V).
The sources (internal and external) and the gain of the video amplifier can be selected via the SDA and SCL pins with
the switching voltage from the AUXILIARY VIDEO/AUDIO plug:
•
Sources I are selected if SDA = 12 V (external source)
•
Sources II are selected if SDA = 0 V (TV mode)
•
Video amplifier gain is 2
×
if SCL = 12 V (external source)
•
Video amplifier gain is 1
×
if SCL = 0 V (TV mode)
If more than one TDA8440 device is used in the non-I
2
C bus system, the OFF pin can be used to switch off the desired
devices. This can be done via the 12 V switching voltage on the AUXILIARY VIDEO/AUDIO plug.
•
All switches are in the OFF position if OFF = H (12 V)
•
All switches are in the selected position via SDA and SCL pins if OFF = L (0 V)
S
1
L
L
H
H
L
L
H
H
S
0
L
H
L
H
L
H
L
H
A
2
0
0
0
0
1
1
1
A
1
0
0
1
1
0
0
1
non I
2
C addressable
A
0
0
1
0
1
0
1
0
November 1985
4
Philips Semiconductors
Product specification
Switch for CTV receivers
I
2
C BUS CONTROL
Detailed information on the I
2
C bus is available on request.
Table 2
STA
TDA8440 I
2
C bus protocol.
A
6
A
5
A
4
A
3
A
2
A
1
A
0
R/W
AC D
7
D
6
D
5
D
4
D
3
D
2
D
1
D
0
TDA8440
AC
STO
STA
A
6
A
5
A
4
A
3
A
2
A
1
A
0
R/W
AC
D
7
D
7
D
6
D
6
D
5
D
5
D
4
D
4
D
3
D
3
D
2
D
2
D
1
D
1
D
0
D
0
STO
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
start condition
1
0
0
1
Fixed address bits
Fixed address bits
Fixed address bits
Fixed address bits
sub-address bit, fixed via S
2
input
sub-address bit, fixed via S
1
input
sub-address bit, fixed via S
0
input
read/write bit (has to be 0, only write mode allowed)
acknowledge bit (= 0) generated by the TDA8440
1 audio la is selected to audio output a
0 audio la is not selected
1 audio lla is selected to audio output a
0 audio lla is not selected
1 audio lb is selected to audio output b
0 audio lb output is not selected
1 audio llb is selected to audio output b
0 audio llb is not selected
1 video l is selected to video output
0 video l is not selected
1 video ll is selected to video output
0 video ll is not selected
1 video amplifier gain is times 2
0 video amplifier gain is times 1
1 OFF-input inactive
0 OFF-input active
stop condition
OFF FUNCTION
With the OFF input all outputs can be switched off (mode high ohmic), depending on the value of D
0
.
November 1985
5
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