TDA4452
TELEFUNKEN Semiconductors
Rev. A1, 15-Aug-96
1 (11)
Video IF Amplifier for Multistandard TV Receiver and VTR
Appliances
Technology: Bipolar
Features
D Standard B/G-L suitable, processes negatively and
positively modulated IF-signals with equal polarity of
the output signal
D Ultra white inverter and ultrablack limiter for
reducing transmission interference
D Internally noise protected gain control, no flyback
pulses required
D Expanded video frequency response allows the
demodulation of amplitude modulated MAC signals
D High input sensitivity
D Minimal intermodulation distortions
D Small differential error
D Fast AGC by controlled discharge of the AGC
capacitor
D Standard L mode: AGC acting on peak white level,
capacitor discharge control by averaged video signal
Standard B/G: AGC acting on the sync. pulse peak
D Constant input impedance
D Video output voltage with narrow tolerance
D Video input/output for insertion of external sound trap
D VTR input/output with video switch
D Adjustable, delayed AGC for the tuner
D ESD protected
Case: DIP18
Figure 1. Block diagram
TDA4452
TELEFUNKEN Semiconductors
Rev. A1, 15-Aug-96
2 (11)
Pin Description
Pin
Function
1,18
IF input
2
Video switch control
3
VTR input, 1 V
PP
4
VTR output, 2 V
PP
(inverted)
5
Supply voltage V
S
6
Video output, 2 V
PP
7
Video input, after sound trap, 2 V
PP
Pin
Function
8,17
Ground
9
Video output, 3 V
PP
from demodulator
10,11
Demodulator circuit
12
standard switch B/G-L
13
Average capacitor standard L
14
Tuner AGC take over
15
AGC (tuner control)
16
IF AGC storage capacitor
Circuit Description
The following functional units are integrated in this
circuit combination for processing multi standard
television IF signals:
The IF signal is supplied to the synchronous demodulator
via a three-stage gain controlled wideband amplifier. A
level detector limits the output voltage of the wideband
amplifier in the event of overdrive.
The required switching carrier for the demodulator is
obtained from the IF signal of the wideband amplifier by
means of a selection and limiter stage. A delay network
is connected upstream of the demodulator in order to
compensate phase differences.
The polarity of the switching carrier at the output of the
limiter stage can be reversed with the standard switch
(Pin 12), with the result that negatively or positively
modulated IF signals appear at the demodulator output
with the same polarity. The demodulated video signal is
filtered and amplified and is supplied to the video output
(Pin 9) via a noise limiter stage.
The standard switch also adapts the operating point of the
video post-amplifier and the IF AGC to the standard
which is to be processed. In the case of standard B/G, the
synchronous peak value acts as the control criterion for
rapid charging and discharge. In contrast, rapid control is
achieved for standard L by charging for ultra white and
discharge by the average (Pin 13) with controlled
reference.
An adjustable control current output (Pin 15) is available
for delayed control of the tuner pre-stage.
A video source switch with 2 inputs is integrated for VTR
applications. The external VTR signal is supplied
capacitively to the input Pin 3 and is clamped to the
synchronous peak value. The second video input Pin 7 is
connected with Pin 9 (video signal from demodulator) via
an external sound trap.
The sound trap must process an attenuation for dc and ac
of 3.5 dB so that the video switch is not overdrived. In
addition, the demodulated video signal is available in in-
verted form as a VTR output signal at Pin 4, independent
of the position of the video switch.
TDA4452
TELEFUNKEN Semiconductors
Rev. A1, 15-Aug-96
3 (11)
Absolute Maximum Ratings
Reference point Pin 8, unless otherwise specified
Parameters
Symbol
Value
Unit
Supply voltage range
Pin 5
V
S
10 to 13.5
V
External voltage
Pin 2, 4, 12, 15
Pin 9, 16
Pin 6
V
2,4,12,15
V
9,16
V
6
V
S
8
6
V
Video output current,max load
Pin 4, 6, 9
I
0
5
mA
Short circuit max 1 s
Pin 4, 6, 9
I
0
30
mA
Junction temperature
T
j
125
C
Ambient temperature range
T
amb
25 to +70
C
Storage temperature range
T
stg
25 to +125
C
Thermal Resistance
Parameters
Symbol
Value
Unit
Junction ambient, in soldered position
R
thJA
60
K/W
Electrical Characteristics
V
S
= +12 V, T
amb
= 25
C, reference point Pin 8, unless otherwise specified
Parameters
Test Conditions / Pins
Symbol
Min.
Typ.
Max.
Unit
Supply voltage
Pin 5
V
S
10
13.5
V
Supply current
Pin 5
I
S
38
44
52
mA
IF amplifier and AGC, Pins 1, 18
Min. input voltage
V
i
70
100
mV
Max. input voltage
V
i
100
120
mV
IF AGC gain reduction
v
p
60
65
dB
Input impedance
R
i
C
i
1.2
2
k
W
pF
Response time of the peak
white control
in standard L
1)
Pin 16
t
r
10
ms
Available tuner AGC
Pin 15
I
15
5
mA
Automatic tuner AGC with
IF control
AGC
61
dB
Demodulator and output stage
2)
, Pin 9
Ultra white level at stan-
dard B/G
V
o
7.1
7.5
7.9
V
Ultra black clamping level
at standard B/G
V
o
4.0
4.2
4.4
V
Composite video output
signal B/G
3)
v
o(pp)
2.7
3.0
3.3
V
Notes:
1)
A peak white value for at least 10
ms must be transmitted for each complete frame
2)
All measurements Pin 9 without load
3)
Residual carrier 10%
TDA4452
TELEFUNKEN Semiconductors
Rev. A1, 15-Aug-96
4 (11)
Parameters
Test Conditions / Pins
Symbol
Min.
Typ.
Max.
Unit
Ultra black level at
standard L
V
0
3.8
4.0
4.2
V
White level at standard L
V
0
6.8
7.2
7.6
V
Video signal standard L
4)
v
0(pp)
1.85
2.1
2.35
V
Output dc current
V
9
= 8 V
I
9
2.5
mA
Difference of the video
signals, standards L and
B/G
10
%
Upsetting factor sync. pulse
DV
Sync
V
Sync
3
%
Tild between black and
white
5
10
%
Clamping level of black
limiter
V
9
250 mV
below sync. (typ)
Threshold of the ultra white
inverter
V
9
900 mV
above ultra white level (typ)
Grey level of the ultra
white inverter
V
9
5.9
V
Video bandwidth (3 dB)
B
video
8.5
10
MHz
Video frequency response
over the AGC range
V
video
2.0
dB
Differential gain error
d
3
%
Differential phase error
3
degree
Sound-chroma beat
(1.07 MHz intermodula-
tion) relating to demodu-
lated auxiliary colour
carrier (figure 3)
video carrier = 0 db
video carrier = 6 db
video carrier = 24 db
a
IM
52
dB
IF residual voltage at the
video output
f = 38.9 MHz
f = 77.8 MHz
v
15
10
mV
Standard switch, Pin 12
Control voltage standard
B/G
V
12
2.4
V
S
V
Control voltage standard L
(Pin 12 not connected;
standard B/G)
V
12
0
1.9
V
Video switch Pin 2
Control voltage for
RF operation
VTR operation (Pin 2 not
connected; VTR operation)
V
2
V
2
2.4
1.9
V
S
V
Clamp level
Pin 3
Pin 7
V
3
V
7
1.4
2.5
V
Composite video output
voltage
1 V
pp
at Pin 3 resp.
2 V
pp
at Pin 7
Pin 6
v
6(pp)
2.0
V
Note:
4)
Blanking level 30% carrier amplitude
TDA4452
TELEFUNKEN Semiconductors
Rev. A1, 15-Aug-96
5 (11)
Parameters
Test Conditions / Pins
Symbol
Min.
Typ.
Max.
Unit
Sync. pulse level
Pin 6
V
6
2.0
V
Video switch bandwidth
3 dB
Pin 6
B
10
MHz
Output current
V
6
= 5 V
Pin 6
I
6
2.0
mA
Cross talk
v
3
= 1 V
Pin 6
50 Hz to 10 MHz sin
v
118
= 0 V, V
2
= 0 V,
V
16
= 4 V
55
dB
VTR output, Pin 4
Composite video output
(inverted)
V
7
= 2 V
pp (peak to peak)
v
4(pp)
2.0
V
Sync. pulse level
V
4
V
S
2.6
V
Output current
V
4
= 10 V
I
4
2.0
mA
Figure 2. Test circuit
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