TB1245N
TENTATIVE
TOSHIBA Bi-CMOS INTEGRATED CIRCUIT
SILICON MONOLITHIC
TB1245N
VIDEO, CHROMA AND SYNCHRONIZING SIGNALS PROCESSING IC FOR
PAL / NTSC / SECAM SYSTEM COLOR TV
TB1245N that is a signal processing IC for the PAL / NTSC /
SECAM color TV system integrates video, chroma and
synchronizing signal processing circuits together in a 56pin
shrink DIP plastic package.
TB1245N incorporates a high performance picture quality
compensation circuit in the video section, an automatic PAL /
NTSC / SECAM discrimination circuit in the chroma section, and
an automatic 50 / 60 Hz discrimination circuit in the
synchronizing section. Besides a crystal oscillator that internally
generates 4.43 MHz, 3.58 MHz and M / N-PAL clock signals for
color demodulation, there is a horizontal PLL circuit built in the
IC.
The PAL / SECAM demodulation circuit which is an
adjustment-free circuit incorporates a 1H DL circuit inside for
operating the base band signal processing system.
Also, TB1245N makes it possible to set or control various
functions through the built-in I
2
C bus line.
Weight: 5.55 g (Typ.)
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TB1245N
FEATURES
=
Video section
·
Built-in trap filter
·
Black expansion circuit
·
Variable DC regeneration rate
·
Y delay line
·
Sharpness control by aperture control
·
γ
correction
=
Chroma section
·
Built-in 1 H Delay circuit
·
PAL base band demodulation
·
One crystal color demodulation circuit
·
Automatic system discrimination
·
Built-in band-pass filter
·
Color limiter circuit
=
Synchronizing deflecting section
·
Built-in horizontal VCO resonator
·
Adjustment-free horizontal / vertical oscillation By count-down circuit
·
Double AFC circuit
·
Vertical frequency automatic discrimination circuit
·
Horizontal / vertical holding adjustment
·
Vertical ramp output
·
Vertical amplitude adjustment
·
Vertical linearity / S-shaped curve adjustment
·
E / W output
=
Text section
·
Linear RGB input
·
OSD RGB input
·
Cut / off-drive adjustment
·
RGB primary signal output
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TB1245N
BLOCK DIAGRAM
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TB1245N
PIN
No.
PIN NAME
FUNCTION
INTERFACE CIRCUIT
INPUT / OUTPUT
SIGNAL
1
SCP OUTPUT
Output terminal of Sand Castle
Pulse. (SCP)
To connect drive resistor for SCP.
2
V-AGC
Controls pin 52 to maintain a
uniform V-ramp output.
Connect a current smoothing
capacitor to this pin.
—
3
H-V
CC
(9 V)
V
CC
for the DEF block (deflecting
system). Connect 9 V (Typ.) to this
pin.
—
—
4
Horizontal Output
Horizontal output terminal.
Corrects picture distortion in high
voltage variation. Input AC
component of high voltage variation.
5
Picture Distortion
Correction
For inactivating the picture distortion
correction function, connect 0.01
µF capacitor between this pin and
GND.
4.5 V at Open
FBP input for generating horizontal
AFC2 detection pulse and horizontal
blanking pulse.
6
FBP Input
The threshold of horizontal AFC2
detection is set H.V
CC
-2V
f
(V
f
≈
0.75 V).
Confirming the power supply
voltage, determine the high level of
FBP.
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2001-07-26
TB1245N
PIN
No.
PIN NAME
FUNCTION
INTERFACE CIRCUIT
INPUT / OUTPUT
SIGNAL
7
Coincident Det.
To connect filter for detecting
presence of H. synchronizing signal
or V. synchronizing signal.
—
8
V
DD
(5 V)
V
DD
terminal of the LOGIC block.
Connect 5 V (Typ.) to this pin.
—
—
9
SCL
SCL terminal of I C bus.
2
—
10
SDA
SDA terminal of I C bus.
2
—
11
Digital GND
Grounding terminal of LOGIC block.
—
—
12
13
14
B Output
G Output
R Output
R, G, B output terminals.
15
TEXT GND
Grounding terminal of TEXT block.
—
―
16
ABCL
External unicolor brightness control
terminal. Sensitivity and start point
of ABL can be set through the bus.
6.4 V at Open
17
RGB-V
CC
(9 V)
V
CC
terminal of TEXT block.
Connect 9 V (Typ.) to this pin.
―
―
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2001-07-26
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