TEA2029 STMICROELECTRONICS [STMicroelectronics], TEA2029 Datasheet - Page 31

• Manufacturer Part Number: TEA2029
• Description: APPLICATION NOTE
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

Figure 61 : Block Diagram
V.7 - SWITCHING POWER SUPPLY DRIVER STAGE
Switching takes place on the primary side (mains
side) of a transformer by using TEA2164 SMPS
Controller manufactured by SGS-THOMSON.
Required voltage values are obtained by rectifying
different voltage outputs delivered through secon-
dary windings. The horizontal deflection stage is
powered by one of these outputs delivering around
hundred volts.
V.7.1 - Power supply block diagram
Figure 62
Frame
Yoke
Mains
Input
(1.26V)
Frame
Yoke
Current
V
1nF
2
100k
Flyback
TEA2164
2
1k
70 A
135V
1.26V
Line Deflection
12V
(no safety)
Blanking
1.26V
Stage
Frame
This voltage source must be regulated since any
voltage fluctuation will yield variations of the hori-
zontal display amplitude.
The TE2028 monitors this voltage and transmits
the regulation signal to the primary controller cir-
cuitry via a small pulse transformer. The charac-
teristics of this regulation signal are directly related
to the conduction period of switching transistor.
P
TEA2028 - TEA2029 APPLICATION NOTE
14
9
7
Window
1.26V
V
Frame
28 s
Reset
(2 s)
REF
1.26V
x 1
&
A
28
FLIP-FLOP
R
S
&
SAFETY
-70 A
Input Characteristics
0
Q
I
M1
2
1 3
1/1k
1
TEA2028B
1.9 V
Sawtooth
1/1k
Frame Blanking
CIRCUITRY
START-UP
M2
(with safety)
Line
V
2
Output
S.S.C.
(Pin 11)
15
4
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