TDA8218 Datasheet, PDF (5/9 Pages) STMicroelectronics – HORIZONTAL AND VERTICAL DEFLECTION CIRCUIT

TDA8218
GENERAL DESCRIPTION
The TDA8218 performs all the video and power
functions required to provide signals for the line
driver and frame yoke.
It contains:
• A synchronization separator
• An integrated frame separator without external
components
Figure 1 : Synchronization Separator Circuit
• A saw-tooth generator for the frame
• A power amplifier for direct drive of frame yoke
(short circuit protected)
• An open collector output for the line driver
• A line phase detector and a voltage control os-
cillator
• A super sandcastle generator.
Video
VR
20
R1
R2
SL1 SL2
The slice level of sync-separation is fixed by value of the external resistors R1 and R2. VR is an internally
fixed voltage.
Figure 2 : Frame Separator
Vz
I
SL1
3I
Q3
ST1
Vz /2
Q4
ST2
The sync-pulse allows the discharge of the capaci-
tor by a 2 x I current. A line sync-pulse is not able
to discharge the capacitor under VZ/2. A frame
sync-pulse permits the complete discharge of the
capacitor, so during the frame sync-pulse Q3 and
Q4 provide current for the other parts of the circuit.
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