tda933xh NXP Semiconductors, tda933xh Datasheet - Page 32

• Manufacturer Part Number: tda933xh
• Description: Tda933xh Series I2c-bus Controlled Tv Display Processors
• Manufacturer: NXP Semiconductors

Philips Semiconductors
25. The set is switched off via the mains power switch. When the mains supply is switched off, the supply voltage of the
26. The discharge current for the picture tube can be increased with an external current division circuit on the black
27. A stable switching of the H
28. The simplified circuit diagram of the oscillator is given in Fig.3. To ensure that the oscillator will start-up, the ceramic
29. Pin HSEL must be connected to ground in a 1f
30. The indicated tolerance on the free-running frequency is only valid when an accurate reference frequency (obtained
31. The correction factor k of the phase-2 loop is defined as the amount of correction per line period of a phase error
32. The control range of the second control loop depends on the line frequency. The maximum control range from the
33. The dynamic phase compensation input (pin 14) is connected to an internal reference voltage of 4.0 V via a resistor
34. The range of parallelogram and bow correction is proportional to the width of the horizontal flyback pulse. For zero
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line deflection circuit of the TV set will decrease. A detection circuit must be made that monitors this supply voltage.
When the supply voltage suddenly decreases, pin FBCSO (fixed beam current switch-off) of the TDA933xH must be
pulled high. In this situation, the procedure is as follows:
a) Vertical scan is completed.
b) Vertical flyback is completed.
c) The fixed beam current is forced via the black current loop (if FBC = 1). The horizontal output keeps running.
d) If OSO = 1, the vertical deflection stays in overscan position; if OSO = 0, the vertical deflection keeps running.
e) When the supply voltage of the TDA933xH drops below the POR level, horizontal output and fixed beam current
current input (pin 44). The current division should only be active for high cathode currents, so that the operation of
the black current stabilization loop is not affected. When the feedback current supplied to pin 44 is less than 1mA,
the DC level at the RGB outputs will go to the maximum value of 6.0 V (2-point black current stabilization) or 5.6 V
(1-point or no black current stabilization).
resonator must fulfil the following condition:
Example: When the resonator is loaded with 60 pF (this is a typical value for a 12 MHz resonator), the series
resistance of the resonator must be smaller than 30 .
A suitable ceramic resonator for use with the TDA933xH is the Murata CST12.0MT, which has built-in load
capacitances C
with respect to start-up because of its lower load capacitance.
TDA9331H and TDA9332H can be switched to a multi-sync mode, in which the horizontal frequency can vary
between 15 and 25 kHz (1f
with an accurate 12 MHz crystal) is used. The tolerance of the reference resonator must be added to obtain the real
tolerance on the free-running frequency.
between the horizontal flyback pulse and the internal phase-2 reference pulse. When k = 0.5, the phase error
between the flyback pulse and the internal reference is halved each line period.
rising edge of HOUT to the centre of the flyback pulse is always 37% of one line period, for the centre position of the
dynamic phase compensation (4.0 V at pin 14).
of 100 k . If dynamic phase compensation is not used, this pin should be decoupled to ground (pin 19) via a
capacitor of 100 nF.
correction, use DAC setting 7 DEC or 0111 (bin). The effect of the corrections is shown in Fig.16.
C-bus controlled TV display processors
As the supply voltage for the line transformer decreases, the EHT voltage will also decrease.
are stopped.
a
and C
b
. For higher accuracy, it is also possible to use a quartz crystal, which is even less critical
D
H
input is realized by using a Schmitt trigger input.
mode) or 30 and 50 kHz (2f
C
2
L
H
application; it must be left open circuit for a 2f
R
i
1.1 10
32
H
mode).
–
19
.
TDA933xH series
Preliminary specification
H
application. The