TEA2029 STMICROELECTRONICS [STMicroelectronics], TEA2029 Datasheet - Page 25

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

Figure 49
High level duration (T10) of Pin 10 output signal
must be higher than the delay interval ”t
the flyback time (i.e. 8 + 12 = 20 s) and must
turn-off before the end of diode conduction :
In practice, one will select the pin 1 capacitor
C1 = 3.3nF to yield T
V.5.3 - Characteristics of loop ” ”
The function to calculate is a time with respect to
the origin time set by ”V ”. In fact, it is an easy task
to inter-relate the horizontal displacement (in mm)
to a time interval specified in s.
For a large screen width of 540mm, the horizontal
scanning time : 64 - 12 = 52 s, which corresponds
to : 10mm/ s.
Figure 50
- i = A . (t
- V = Z i +
- t
V
OUT
2
t
IN
t
- t
IN
T
IN
V
(Tr)
10
IN
V
CE
I
I
LF
I
10
Tr
D
= B V + t
0
0
0
0
0
Y
< t
- t
Z
R
t
OUT
S(Min.)
S Correction
OUT
12V
t
K V
)(1)
A
Tr C
+ t
CC
d
10
(turn-off delay)
i
- 59.7 s
LF
= 29 s.
- Z I
C
f(p)
t
+
S
D
t
V
trace
IN
2
12 s
B
T
29 s
10
(2)
(3)
< 40 s
Delay
t ( )
d
t
t
t
t
t
S(MAX)
Scanning
Flyback
Middle
of
t
OUT
” +
- Z =
- R’ = R
- A = 17 A/ s
-
- B = 16.4 s/V
The open-loop dynamic gain is :
The system exhibits the characteristics inherent to
a first order circuit and is therefore stable.
Combining equations (1), (2), (3) and (4), the t
delay is found as follows :
It is therefore clear that the second phase-locked
loop does not cause any dynamic delay.
This can be explained by the fact that the phase
modulator responds instanenouslyto all variations
of ” ”.
V.5.3.1 - Study of the Static Error
t
The equivalent impedance of F(p) filter is :
- R’ = 460k (R // R
- Modulator input resistance RIN = 25M : without
A. PHASE SHIFT ERROR IN CASE OF
NO ADJUSTMENT
Equation (5) becomes :
with : T1 = ABR
Where :
- R
- I
- t
- T1 = 6.8 10
The error is quite negligible and thanks to rather
high open-loop gain, the display accuracy with
respect to the phase set by ”
TEA2028 - TEA2029 APPLICATION NOTE
IN
t
to Pin 16, or
adjustment
IN
d
OUT
= 0 (phase of V ) is taken as timing reference.
IN
= R’C
= 10 s
= 0.65mA
= 25M
1
Dynamic
gain = 1
= t
R
IN
T = ABf(p) = ABZ =
IN
// R
T
p
OUT
input current
3
Error term
due to the
BZI
1 + T
=
IN
= 76dB
”I
BR
IN
1
IN
IN
”
IN
) : if an adjustment is applied
+
T
I
1
IN
t
due to delay
D
Error term
t
which corresponds to a
picture shift of 0.46mm !
+
OUT
1 + T
59.7 s
t
1
2
ABR
D
”, is very satisfactory.
= - 46ns
1
59.7 s
p
T
+
1
Error term due
B
to phase shift
(if applicable)
(4)
adjustment
Z
R
1 + T
KV
25/46
OUT
CC