TDA4856/V6,112 NXP Semiconductors, TDA4856/V6,112 Datasheet - Page 9

• Manufacturer Part Number: TDA4856/V6,112
• Manufacturer: NXP Semiconductors

Specifications of TDA4856/V6,112

• Lead Free Status / RoHS Status: Compliant

Philips Semiconductors
X-ray protection
The X-ray protection input XRAY (pin 2) provides a voltage
detector with a precise threshold. If the input voltage at
XRAY exceeds this threshold for a certain period of time,
control bit SOFTST is reset, which switches the IC into
protection mode. In this mode several pins are forced into
defined states:
There are two different ways to restart the IC:
1. XSEL (pin 9) is open-circuit or connected to ground.
2. XSEL is connected to V
Vertical oscillator and amplitude control
This stage is designed for fast stabilization of vertical size
after changes in sync frequency conditions.
The free-running frequency f
resistor R
C
optimized for noise and linearity performance in the whole
vertical and EW section, but also influences several
internal references. Therefore the value of R
be changed. Capacitor C
free-running frequency of the vertical oscillator in
accordance with the following formula:
To achieve a stabilized amplitude the free-running
frequency f
lower than the minimum trigger frequency.
The contributions shown in Table 2 can be assumed.
2003 Sep 30
f
VCAP
fr(V)
HUNLOCK (pin 17) is floating
The capacitor connected to HPLL2 (pin 30) is
discharged
Horizontal output stage (HDRV) is floating
B+ control driver stage (BDRV) is floating
CLBL provides a continuous blanking signal.
I
PC monitors
2
The control bit SOFTST must be set to logic 1 via the
I
soft start.
The supply voltage of the IC must be switched off for a
certain time before the IC can be restarted again using
the standard power-on procedure.
2
C-bus autosync deflection controller for
C-bus. The IC then returns to normal operation via
=
connected to pin 24. The value of R
---------------------------------------------------------- -
10.8 R
VREF
fr(V)
, without adjustment, should be at least 10%
connected to pin 23 and the capacitor
VREF
1
VCAP
C
VCAP
CC
fr(V)
should be used to select the
via an external resistor.
is determined by the
VREF
VREF
is not only
must not
9
Table 2 Calculation of f
Result for 50 to 160 Hz application:
The AGC of the vertical oscillator can be disabled by
setting control bit AGCDIS via the I
external current has to be injected into VCAP (pin 24) to
obtain the correct vertical size. This special application
mode can be used when the vertical sync pulses are
serrated (shifted); this condition is found in some display
modes, e.g. when using a 100 Hz upconverter for video
signals.
Application hint: VAGC (pin 22) has a high input
impedance during scan. Therefore, the pin must not be
loaded externally; otherwise non-linearities in the vertical
output currents may occur due to the changing charge
current during scan.
Adjustment of vertical size, VGA overscan and EHT
compensation
There are four different ways to adjust the amplitude of the
differential output currents at VOUT1 and VOUT2:
1. Register VGAIN changes the vertical size without
2. Register VSIZE changes not only the vertical size, but
3. For the VGA350 mode the register VOVSCN can
4. VSMOD (pin 21) can be used for a DC controlled EHT
Minimum frequency offset between f
lowest trigger frequency
Spread of IC
Spread of R
Spread of C
Total
f
fr(V)
affecting any other output signal of the IC; this
adjustment is meant for factory alignments.
also provides the correct tracking of all other related
waveforms (see Section “Tracking of vertical
adjustments”); this register should be used for user
adjustments.
activate a +17% step in vertical size.
compensation of vertical size by correcting the
differential output currents at VOUT1 and VOUT2;
VSMOD does not affect the EW waveforms, vertical
focus, pin unbalance and parallelogram corrections.
=
50 Hz
-------------- -
1.19
Contributing elements
VREF
VCAP
=
42 Hz
fr(V)
total spread
2
C-bus. A precise
Product specification
fr(V)
TDA4856
and
10%
19%
3%
1%
5%