• Multi-standard vision IF circuit with an alignment-free
PLL demodulator without external components
• Alignment-free multi-standard FM sound demodulator
(4.5 MHz to 6.5 MHz)
• Audio switch
• Flexible source selection with CVBS switch and
Y(CVBS)/C input so that a comb filter can be applied
• Integrated chrominance trap circuit
• Integrated luminance delay line
• Asymmetrical peaking in the luminance channel with a
(defeatable) noise coring function
• Black stretching of non-standard CVBS or luminance
signals
• Integrated chroma band-pass filter with switchable
centre frequency
• Dynamic skin tone control circuit
• Blue stretch circuit which offsets colours near white
towards blue
• RGB control circuit with “Continuous Cathode
Calibration” and white point adjustment
• Possibility to insert a “blue back” option when no video
signal is available
• Horizontal synchronization with two control loops and
alignment-free horizontal oscillator
• Vertical count-down circuit
• Vertical driver optimised for DC-coupled vertical output
stages
• I2C-bus control of various functions
The detailed differences between the various IC’s are
given in the table on page 3.
TDA884X/5X-N2 series
GENERAL DESCRIPTION
The various versions of the TDA 884X/5X series are
I2C-bus controlled single chip TV processors which are
intended to be applied in PAL, NTSC, PAL/NTSC and
multi-standard television receivers. The N2 version is pinand application compatible with the N1 version, however,a new feature has been added which makes the N2 moreattractive. The IF PLL demodulator has been replaced byan alignment-free IF PLL demodulator with internal VCO(no tuned circuit required). The setting of the various
frequencies (33.4, 33.9, 38, 38.9, 45,75 and 58.75 MHz)
can be made via the I2C-bus.
Because of this difference the N2 version is compatiblewith the N1, however, N1 devices cannot be used in anoptimised N2 application.
Functionally the IC series is split up is 3 categories, viz:
• Versions intended to be used in economy TV receivers
with all basic functions (envelope: S-DIP 56 and QFP
64)
• Versions with additional features like E-W geometry
control, H-V zoom function and YUV interface which are
intended for TV receivers with 110° picture tubes
(envelope: S-DIP 56)
• Versions which have in addition a second RGB input
with saturation control and a second CVBS output
(envelope: QFP 64)
The various type numbers are given in the table below.
SURVEY OF IC TYPES
ENVELOPES-DIP 56QFP 64
TV receiver categoryEconomyMid/High endEconomyMid/High end
PAL onlyTDA 8840TDA 8840H
PAL/NTSCTDA 8841TDA 8843TDA 8841H
PAL/SECAM/NTSCTDA 8842TDA 8844TDA 8842HTDA 8854H
NTSC onlyTDA 8846/46ATDA 8847TDA 8857H
FUNCTIONAL DIFFERENCES BETWEEN THE VARIOUS IC VERSIONS
IC VERSION (TDA)88408841884288468846A8843884488478854H8857H
Automatic Volume LimitingXXXXX
PAL decoderXXXXXX
SECAM decoderXXX
NTSC decoderXXXXXXXXX
Colour matrix PAL/NTSC(Japan)XXXXX
Colour matrix NTSC Japan/USAXXXX
YUV interfaceXXXXXXX
Base-band delay line for P AL and
demodulated CVBS output (peak-to-peak value)−2.2−V
tuner AGC output current range0−5mA
CVBS1/CVBS2 output voltage of video switch
−2.0/1.0−V
(peak-to-peak value)
−(R−Y) output/input voltage (peak-to-peak value)−1.05−V
−(B−Y) output/input voltage (peak-to-peak value)−1.33−V
Y output/input voltage (peak-to-peak value)−1.4−V
RGB output signal amplitudes (peak-to-peak value)−2.0−V
horizontal output current10−−mA
vertical output current (peak-to-peak value)−1−mA
EW drive output current1.2−−mA
DECDIG3955Decoupling digital supply
HOUT4056horizontal output
FBISO4157flyback input/sandcastle output
PH2LF4258phase-2 filter
PH1LF4359phase-1 filter
GND24460ground 2
EWD4562east-west drive output
VDRB4663vertical drive B output
VDRA4764vertical drive A output
IFIN1481IF input 1
IFIN2492IF input 2
EHTO503EHT/overvoltage protection input
VSC514vertical sawtooth capacitor
I
ref
DEC
AGC
AGCOUT547tuner AGC output
AUDEEM558Audio deemphasis
DECSDEM569Decoupling sound demodulator
n.c.−12not connected
VP3−23Main supply voltage 2 (+8V)
CVBS2O−26CVBS-2 output
RI2−412nd R input
GI2.−422nd G input
BI2−432nd B input
RGBIN2−442nd RGB insertion input
GND3−61ground 3
SDIP56QFP64
525reference current input
536AGC decoupling capacitor
PIN
DESCRIPTION
The pin numbers mentioned in the rest of this document are referenced to the SDIP56 (SOT400) package.
In the TDA 8840/41/42/46/46A the following pins are different:
Pin 16 (SECAM PLL decoupling): Not connected in the TDA 8840/41/46/46A
Pin 27: Not connected in TDA 8840/41/42
Pin 28: Luminance output in TDA 8840/41/42
Pin 29-32 (U/V interface): Not available in TDA 8840/41/42
Pin 35 (4.43 MHz X-tal): Not connected in the TDA 8846/46A
Pin 45 (E-W drive output): AVL capacitor
In the TDA 8857H the pins 28 (SECAM PLL decoupling) and 51 (4.43 MHz X-tal) are not connected.
The IF-amplifier contains 3 ac-coupled control stages with
a total gain control range which is higher then 66 dB. The
sensitivity of the circuit is comparable with that of modern
IF-IC’s.
The video signal is demodulated by means of an
alignment-free PLL carrier regenerator with an internal
VCO. This VCO is calibrated by means of a digital control
circuit which uses the X-tal frequency of the colour
decoder as a reference. The frequency setting for the
various standards (33.4, 33.9, 38, 38.9, 45.75 and 58.75
MHz) is realised via the I
performance for phase modulated carrier signals the
control speed of the PLL can be increased by means of the
FFI bit.
The AFC output is generated by the digital control circuit of
the IF-PLL demodulator and can be read via the I2C-bus.
For fast search tuning systems the window of the AFC can
be increased with a factor 3. The setting is realised with the
AFW bit. The AFC data is valid only when the horizontal
PLL is in lock (SL = 1)
Depending on the type the AGC-detector operates on
top-sync level (single standard versions) or on top sync
and top white- level (multi standard versions). The
demodulation polarity is switched via the I2C-bus. The
AGC detector time-constant capacitor is connected
externally. This mainly because of the flexibility of the
application. The time-constant of the AGC system during
positive modulation is rather long to avoid visible variations
2
C-bus. To get a good
TDA884X/5X-N2 series
of the signal amplitude. To improve the speed of the AGC
system a circuit has been included which detects whether
the AGC detector is activated every frame period. When
during 3 field periods no action is detected the speed of the
system is increased. For signals without peak white
information the system switches automatically to a gated
black level AGC. Because a black level clamp pulse is
required for this way of operation the circuit will only switch
to black level AGC in the internal mode.
The circuits contain a video identification circuit which is
independent of the synchronisation circuit. Therefore
search tuning is possible when the display section of the
receiver is used as a monitor. However, this ident circuit
cannot be made as sensitive as the slower sync ident
circuit (SL) and we recommend to use both ident outputs
to obtain a reliable search system. The ident output is
supplied to the tuning system via the I2C-bus.
The input of the identification circuit is connected to pin 13
(S-DIP 56 devices), the “internal” CVBS input (see Fig.6).
This has the advantage that the ident circuit can also be
made operative when a scrambled signal is received
(descrambler connected between pin 6 (IF video output)
and pin 13). A second advantage is that the ident circuit
can be used when the IF amplifier is not used (e.g. with
built-in satellite tuners).
The video ident circuit can also be used to identify the
selected CBVS or Y/C signal. The switching between the
2 modes can be realised with the VIM bit.
The circuits have two CVBS inputs (internal and external
CVBS) and a Y/C input. When the Y/C input is not required
the Y input can be used as third CVBS input. The switch
configuration is given in Fig.6. The selection of the various
sources is made via the I2C-bus.
For the TDA 884X devices the video switch configuration
is identical to the switch of the TDA 8374/75 series. So the
circuit has one CVBS output (amplitude of 2 V
TDA 884X series) and the I2C-bus control is similar to that
of the TDA 8374/75. For the TDA 885X IC’s the video
switch circuit has a second output (amplitude of 1 V
which can be set independently of the position of the first
output. The input signal for the decoder is also available on
the CVBS1-output.
Therefore this signal can be used to drive the Teletext
decoder. If S-VHS is selected for one of the outputs the
luminance and chrominance signals are added so that a
CVBS signal is obtained again.
Sound circuit
The sound bandpass and trap filters have to be connected
externally. The filtered intercarrier signal is fed to a limiter
circuit and is demodulated by means of a PLL
demodulator. This PLL circuit tunes itself automatically to
the incoming carrier signal so that no adjustment is
required.
The volume is controlled via the I2C-bus. The deemphasis
capacitor has to be connected externally. The
non-controlled audio signal can be obtained from this pin
(via a buffer stage).
The FM demodulator can be muted via the I2C-bus. This
function can be used to switch-off the sound during a
channel change so that high output peaks are prevented.
The TDA 8840/41/42/46 contain an Automatic Volume
Levelling (AVL) circuit which automatically stabilises the
audio output signal to a certain level which can be set by
the viewer by means of the volume control. This function
prevents big audio output fluctuations due to variations of
the modulation depth of the transmitter. The AVL function
can be activated via the I2C-bus.
Synchronisation circuit
The sync separator is preceded by a controlled amplifier
which adjusts the sync pulse amplitude to a fixed level.
These pulses are fed to the slicing stage which is operating
at 50% of the amplitude. The separated sync pulses are
fed to the first phase detector and to the coincidence
detector. This coincidence detector is used to detect
P-P
for the
P-P
)
TDA884X/5X-N2 series
whether the line oscillator is synchronised and can also be
used for transmitter identification. This circuit can be made
less sensitive by means of the STM bit. This mode can be
used during search tuning to avoid that the tuning system
will stop at very weak input signals. The first PLL has a
very high statical steepness so that the phase of the
picture is independent of the line frequency.
The horizontal output signal is generated by means of an
oscillator which is running at twice the line frequency. Its
frequency is divided by 2 to lock the first control loop to the
incoming signal. The time-constant of the loop can be
forced by the I2C-bus (fast or slow). If required the IC can
select the time-constant depending on the noise content of
the incoming video signal.
The free-running frequency of the oscillator is determined
by a digital control circuit which is locked to the reference
signal of the colour decoder. When the IC is switched-on
the horizontal output signal is suppressed and the
oscillator is calibrated as soon as all sub-address bytes
have been sent. When the frequency of the oscillator is
correct the horizontal drive signal is switched-on. To obtain
a smooth switching-on and switching-off behaviour of the
horizontal output stage the horizontal output frequency is
doubled during switch-on and switch-off (slow start/stop).
During that time the duty cycle of the output pulse has such
a value that maximum safety is obtained for the output
stage.
To protect the horizontal output transistor the horizontal
drive is immediately switched off when a power-on-reset is
detected. The drive signal is switched-on again when the
normal switch-on procedure is followed, i.e. all
sub-address bytes must be sent and after calibration the
horizontal drive signal will be released again via the slow
start procedure. When the coincidence detector indicates
an out-of-lock situation the calibration procedure is
repeated. The circuit has a second control loop to generate
the drive pulses for the horizontal driver stage. The
horizontal output is gated with the flyback pulse so that the
horizontal output transistor cannot be switched-on during
the flyback time.
Via the I2C-bus adjustments can be made of the horizontal
and vertical geometry. The vertical sawtooth generator
drives the vertical output drive circuit which has a
differential output current. For the E-W drive a single
ended current output is available. A special feature is the
zoom function for both the horizontal and vertical
deflection and the vertical scroll function which are
available in some versions. When the horizontal scan is
reduced to display 4:3 pictures on a 16:9 picture tube an
accurate video blanking can be switched on to obtain well
defined edges on the screen.
Overvoltage conditions (X-ray protection) can be detected
via the EHT tracking pin. When an overvoltage condition is
detected the horizontal output drive signal will be
switched-off via the slow stop procedure but it is also
possible that the drive is not switched-off and that just a
protection indication is given in the I2C-bus output byte.
The choice is made via the input bit PRD. The IC’s have a
second protection input on theϕ2 filter capacitor pin. When
this input is activated the drive signal is switched-off
immediately and switched-on again via the slow start
procedure. For this reason this protection input can be
used as “flash protection”.
The drive pulses for the vertical sawtooth generator are
obtained from a vertical countdown circuit. This countdown
circuit has various windows depending on the incoming
signal (50 Hz or 60 Hz and standard or non standard). The
countdown circuit can be forced in various modes by
means of the I2C-bus. During the insertion of RGB signals
the maximum vertical frequency is increased to 72 Hz so
that the circuit can also synchronise on signals with a
higher vertical frequency like VGA. To obtain short
switching times of the countdown circuit during a channel
change the divider can be forced in the search window by
means of the NCIN bit. The vertical deflection can be set
in the de-interlace mode via the I2C bus.
To avoid damage of the picture tube when the vertical
deflection fails the guard output current of the TDA
8350/51 can be supplied to the beam current limiting input.
When a failure is detected the RGB-outputs are blanked
and a bit is set (NDF) in the status byte of the I2C-bus.
When no vertical deflection output stage is connected this
guard circuit will also blank the output signals. This can be
overruled by means of the EVG bit.
TDA884X/5X-N2 series
The resolution of the peaking control DAC has been
increased to 6 bits. All IC’s have a defeatable coring
function in the peaking circuit. Some of these IC’s have a
YUV interface (see table on page 2) so that picture
improvement IC’s like the TDA 9170 (Contrast
improvement), TDA 9177 (Sharpness improvement) and
TDA 4556/66 (CTI) can be applied. When the CTI IC’s are
applied it is possible to increase the gain of the luminance
channel by means of the GAI bit in subaddress 03 so that
the resulting RGB output signals are not affected.
Colour decoder
Depending on the IC type the colour decoder can decode
PAL, PAL/NTSC or PAL/NTSC/SECAM signals. The
PAL/NTSC decoder contains an alignment-free X-tal
oscillator, a killer circuit and two colour difference
demodulators. The 90° phase shift for the reference signal
is made internally.
The IC’s contain an Automatic Colour Limiting (ACL)
circuit which is switchable via the I2C-bus and which
prevents that oversaturation occurs when signals with a
high chroma-to-burst ratio are received. The ACL circuit is
designed such that it only reduces the chroma signal and
not the burst signal. This has the advantage that the colour
sensitivity is not affected by this function.
The SECAM decoder contains an auto-calibrating PLL
demodulator which has two references, viz: the 4.4 MHz
sub-carrier frequency which is obtained from the X-tal
oscillator which is used to tune the PLL to the desired
free-running frequency and the bandgap reference to
obtain the correct absolute value of the output signal. The
VCO of the PLL is calibrated during each vertical blanking
period, when the IC is in search or SECAM mode.
Chroma and luminance processing
The circuits contain a chroma bandpass and trap circuit.
The filters are realised by means of gyrator circuits and
they are automatically calibrated by comparing the tuning
frequency with the X-tal frequency of the decoder. The
luminance delay line and the delay for the peaking circuit
are also realised by means of gyrator circuits. The centre
frequency of the chroma bandpass filter is switchable via
the I2C-bus so that the performance can be optimised for
“front-end” signals and external CVBS signals. During
SECAM reception the centre frequency of the chroma trap
is reduced to get a better suppression of the SECAM
carrier frequencies. All IC’s have a black stretcher circuit
which corrects the black level for incoming video signals
which have a deviation between the black level and the
blanking level (back porch). The timeconstant for the black
stretcher is realised internally.
December 16, 199714
The frequency of the active X-tal is fed to the Fsc output
(pin 33) and can be used to tune an external comb filter
(e.g. the SAA 4961).
The base-band delay line (TDA 4665 function) is
integrated in the PAL/SECAM IC’s and in the NTSC IC
TDA 8846A. In the latter IC it improves the cross colour
performance (chroma comb filter). The demodulated
colour difference signals are internally supplied to the
delay line. The colour difference matrix switches
automatically between PAL/SECAM and NTSC, however,
it is also possible to fix the matrix in the PAL standard.
The “blue stretch” circuit is intended to shift colour near
“white” with sufficient contrast values towards more blue to
obtain a brighter impression of the picture.
Which colour standard the IC’s can decode depends on
the external X-tals. The X-tal to be connected to pin 34
must have a frequency of 3.5 MHz (NTSC-M, PAL-M or
PAL-N) and pin 35 can handle X-tals with a frequency of
4.4 and 3.5 MHz. Because the X-tal frequency is used to
tune the line oscillator the value of the X-tal frequency
must be given to the IC via the I2C-bus. It is also possible
to use the IC in the so called “Tri-norma” mode for South
America. In that case one X-tal must be connected to pin
34 and the other 2 to pin 35. The switching between the 2
latter X-tals must be done externally. This has the
consequence that the search loop of the decoder must be
controlled by the µ-computer. To prevent calibration
problems of the horizontal oscillator the external switching
between the 2 X-tals should be carried out when the
oscillator is forced to pin 34. For a reliable calibration of the
horizontal oscillator it is very important that the X-tal
indication bits (XA and XB) are not corrupted. For this
reason the X-tal bits can be read in the output bytes so that
the software can check the I2C-bus transmission.
Under bad-signal conditions (e.g. VCR-playback in feature
mode), it may occur that the colour killer is activated
although the colour PLL is still in lock. When this killing
action is not wanted it is possible to overrule the colour
killer by forcing the colour decoder to the required standard
and to activate the FCO-bit (Forced Colour On) in the
control-5 subaddress.
The IC’s contain a so-called “Dynamic skin tone (flesh)
control” feature. This function is realised in the YUV
domain by detecting the colours near to the skin tone. The
correction angle can be controlled via the I2C-bus.
RGB output circuit and black-current stabilisation
The colour-difference signals are matrixed with the
luminance signal to obtain the RGB-signals. The TDA
884X devices have one (linear) RGB input. This RGB
signal can be controlled on contrast and brightness (like
TDA 8374/75). By means of the IE1 bit the insertion
blanking can be switched on or off. Via the IN1 bit it can be
read whether the insertion pin has a high level or not.
The TDA 885X IC’s have an additional RGB input. This
RGB signal can be controlled on contrast, saturation and
brightness. The insertion blanking of this input can be
switched-off by means of the IE2 bit. Via the IN2 bit it can
be read whether the insertion pin has a high level or not.
TDA884X/5X-N2 series
The output signal has an amplitude of about 2 volts
black-to-white at nominal input signals and nominal
settings of the controls. To increase the flexibility of the IC
it is possible to insert OSD and/or teletext signals directly
at the RGB outputs. This insertion mode is controlled via
the insertion input (pin 26 in the S-DIP 56- and pin 38 in the
QFP-64 envelope). This blanking action at the RGB
outputs has some delay which must be compensated
externally.
To obtain an accurate biasing of the picture tube a
“Continuous Cathode Calibration” circuit has been
developed. This function is realised by means of a 2-point
black level stabilisation circuit. By inserting 2 test levels for
each gun and comparing the resulting cathode currents
with 2 different reference currents the influence of the
picture tube parameters like the spread in cut-off voltage
can be eliminated. This 2-point stabilisation is based on
the principle that the ratio between the cathode currents is
coupled to the ratio between the drive voltages according
to:
γ
k1
k2
=
V
dr1
----------V
dr2
I
------ I
The feedback loop makes the ratio between the cathode
currents Ik1 and Ik2 equal to the ratio between the
reference currents (which are internally fixed) by changing
the (black) level and the amplitude of the RGB output
signals via 2 converging loops. The system operates in
such a way that the black level of the drive signal is
controlled to the cut-off point of the gun so that a very good
grey scale tracking is obtained. The accuracy of the
adjustment of the black level is just dependent on the ratio
of internal currents and these can be made very accurately
in integrated circuits. An additional advantage of the
2-point measurement is that the control system makes the
absolute value of Ik1 and Ik2 identical to the internal
reference currents. Because this adjustment is obtained
by means of an adaption of the gain of the RGB control
stage this control stabilises the gain of the complete
channel (RGB output stage and cathode characteristic).
As a result variations in the gain figures during life will be
compensated by this 2-point loop.
An important property of the 2-point stabilisation is that the
off-set as well as the gain of the RGB path is adjusted by
the feedback loop. Hence the maximum drive voltage for
the cathode is fixed by the relation between the test
pulses, the reference current and the relative gain setting
of the 3 channels. This has the consequence that the drive
level of the CRT cannot be adjusted by adapting the gain
of the RGB output stage. Because different picture tubes
may require different drive levels the typical “cathode drive
level” amplitude can be adjusted by means of an I2C-bus
setting. Dependent on the chosen cathode drive level the
typical gain of the RGB output stages can be fixed taking
into account the drive capability of the RGB outputs (pins
19 to 21). More details about the design will be given in the
application report.
The measurement of the “high” and the “low” current of the
2- point stabilisation circuit is carried out in 2 consecutive
fields. The leakage current is measured in each field. The
maximum allowable leakage current is 100 µA
When the TV receiver is switched-on the RGB output
signals are blanked and the black current loop will try to set
the right picture tube bias levels. Via the AST bit a choice
can be made between automatic start-up or a start-up via
the µ-processor. In the automatic mode the RGB drive
signals are switched-on as soon as the black current loop
has been stabilised. In the other mode the BCF bit is set to
0 when the loop is stabilised. The RGB drive can than be
switched-on by setting the AST bit to 0. In the latter mode
some delay can be introduced between the setting of the
BCF bit and the switching of the AST bit so that switch-on
effects can be suppressed.
It is also possible to start-up the devices with a fixed
internal delay (as with the TDA 837X and the TDA884X/5X
N1). This mode is activated with the BCO bit.
The vertical blanking is adapted to the incoming CVBS
signal (50 Hz or 60 Hz). When the flyback time of the
vertical output stage is longer than the 60 Hz blanking time
the blanking can be increased to the same value as that of
the 50 Hz blanking. This can be set by means of the LBM
bit.
TDA884X/5X-N2 series
For an easy (manual) adjustment of the Vg2 control voltage
the VSD bit is available. When this bit is activated the black
current loop is switched-off, a fixed black level is inserted
at the RGB outputs and the vertical scan is switched-off so
that a horizontal line is displayed on the screen. This line
can be used as indicator for the Vg2 adjustment. Because
of the different requirements for the optimum cut-off
voltage of the picture tube the RGB output level is
adjustable when the VSD bit is activated. The control
range is 2.5 ± 0.7 V and can be controlled via the
brightness control DAC.
It is possible to insert a so called “blue back” back-ground
level when no video is available. This feature can be
activated via the BB bit in the control2 subaddress.
2
C-BUS SPECIFICATION
I
The slave address of the IC’s is given in Fig.7. The circuit
operates up to clock frequencies of 400 kHz.
handbook, halfpage
Start-up procedure
Read the status bytes until POR =0 and send all
subaddress bytes. The horizontal output signal is
switched-on when the oscillator is calibrated.
Each time before the data in the IC is refreshed, the status
bytes must be read. If POR =1, the procedure mentioned
above must be carried out to restart the IC.
When this procedure is not followed the horizontal
frequency may be incorrect after power-up or after a
power dip.
Valid subaddresses: 00 to 1A (subaddresses 04 to 07 and 17 are not used), subaddress FE is reserved for test purposes.
Auto-increment mode available for subaddresses. The bit L’FA is only valid in the TDA 8842, the function of the colour
mode bits (CM0-CM2 and CD0-CD2) is dependent on the functional content of the IC.
Table 1 Input status bits.
FUNCTION
Control 000INAINBINCBCOFOAFOBXAXB
Control 101FORF FORSDLSTBPOCCM2CM1CM0
Hue02AVLAKBA5A4A3A2A1A0
Horizontal shift (HS)03VIMGAIA5A4A3A2A1A0
Vertical slope (VS)08NCINSTMA5A4A3A2A1A0
Vertical amplitude (VA)09VIDLBMA5A4A3A2A1A0
S-correction (SC)0A0EVGA5A4A3A2A1A0
Vertical shift (VSH)0BSBLPRDA5A4A3A2A1A0
White point R0C00A5A4A3A2A1A0
White point G0D00A5A4A3A2A1A0
White point B0EMAT0A5A4A3A2A1A0
Peaking0F00A5A4A3A2A1A0
Brightness10RBLCORA5A4A3A2A1A0
Saturation11IE10A5A4A3A2A1A0
Contrast12AFWIFSA5A4A3A2A1A0
AGC take-over13MODVSWA5A4A3A2A1A0
Volume control14SMFAVA5A4A3A2A1A0
Adjustment IF-PLL15IFAIFBIFC00000
Control 218OSOVSDCBBLSBKS00BB
Control 319HOBBPSACLCMBASTCL2CL1CL0
Control 41A0000DSDSAFFIEBS
Control 51B0000000FCO
Valid subaddresses: 00 to 1A, subaddress FE is reserved for test purposes. Auto-increment mode available for
subaddresses. The bits L’FA, CM0-CM2 and CD0-CD2 are only available in the TDA 8843/44.
Table 3 Input status bits.
FUNCTION
Control 000INAINBINCBCOFOAFOBXAXB
Control 101FORF FORSDLSTBPOCCM2CM1CM0
Hue02HBLAKBA5A4A3A2A1A0
Horizontal shift (HS)03VIMGAIA5A4A3A2A1A0
EW width (EW)0400A5A4A3A2A1A0
EW parabola/width (PW)0500A5A4A3A2A1A0
EW corner parabola (CP)0600A5A4A3A2A1A0
EW trapezium (TC)0700A5A4A3A2A1A0
Vertical slope (VS)08NCINSTMA5A4A3A2A1A0
Vertical amplitude (VA)09VIDLBMA5A4A3A2A1A0
S-correction (SC)0AHCOEVGA5A4A3A2A1A0
Vertical shift (VSH)0BSBLPRDA5A4A3A2A1A0
White point R0C00A5A4A3A2A1A0
White point G0D00A5A4A3A2A1A0
White point B0EMAT0A5A4A3A2A1A0
Peaking0F00A5A4A3A2A1A0
Brightness10RBLCORA5A4A3A2A1A0
Saturation11IE10A5A4A3A2A1A0
Contrast12AFWIFSA5A4A3A2A1A0
AGC take-over13MODVSWA5A4A3A2A1A0
Volume control14SMFAVA5A4A3A2A1A0
Adjustment IF-PLL15IFAIFBIFC00000
Vertical zoom (VX)1600A5A4A3A2A1A0
Vertical scroll1700A5A4A3A2A1A0
Control 218OSOVSDCBBLSBKS00BB
Control 319HOBBPSACLCMBASTCL2CL1CL0
Control 41AYD3YD2YD1YD0DSDSAFFIEBS
Control 51B0000000FCO
Valid subaddresses: 00 to 1A, subaddress FE is reserved for test purposes. Auto-increment mode available for
subaddresses. The bits L’FA, CM0-CM2 and CD0-CD2 are only available in the TDA 8854.
Table 5 Input status bits.
FUNCTION
Control 000INAINBINCBCOFOAFOBXAXB
Control 101FORF FORSDLSTBPOCCM2CM1CM0
Hue02HBLAKBA5A4A3A2A1A0
Horizontal shift (HS)03VIMGAIA5A4A3A2A1A0
EW width (EW)0400A5A4A3A2A1A0
EW parabola/width (PW)0500A5A4A3A2A1A0
EW corner parabola (CP)0600A5A4A3A2A1A0
EW trapezium (TC)0700A5A4A3A2A1A0
Vertical slope (VS)08NCINSTMA5A4A3A2A1A0
Vertical amplitude (VA)09VIDLBMA5A4A3A2A1A0
S-correction (SC)0AHCOEVGA5A4A3A2A1A0
Vertical shift (VSH)0BSBLPRDA5A4A3A2A1A0
White point R0C00A5A4A3A2A1A0
White point G0D00A5A4A3A2A1A0
White point B0EMAT0A5A4A3A2A1A0
Peaking0F00A5A4A3A2A1A0
Brightness10RBLCORA5A4A3A2A1A0
Saturation11IE1IE2A5A4A3A2A1A0
Contrast12AFWIFSA5A4A3A2A1A0
AGC take-over13MODVSWA5A4A3A2A1A0
Volume control14SMFAVA5A4A3A2A1A0
Adjustment IF-PLL15IFAIFBIFC00000
Vertical zoom (VX)1600A5A4A3A2A1A0
Vertical scroll1700A5A4A3A2A1A0
Control 218OSOVSDCBBLSBKSCS1CS0BB
Control 319HOBBPSACLCMBASTCL2CL1CL0
Control 41AYD3YD2YD1YD0DSDSAFFIEBS
Control 51B0000000FCO
Table 53 Start-up mode of black current loop; note 1
ASTMODE
0automatic mode;
1switch-on under control of µ-processor
TDA884X/5X-N2 series
Table 54 Cathode drive level
CL2CL1 CL0
00057V
00163 V
01070 V
01177 V
10084 V
10191 V
11099 V
111107 V
Note
1. The given values are valid for the following conditions:
- Nominal CVBS input signal
- Settings for contrast, WPA and peaking nominal
- Black- and blue-stretch switched-off
- Gain of output stage such that no clipping occurs
- Beam current limiting not active
The tolerance on these values is about ± 3 V.
SETTING CATHODE DRIVE
AMPLITUDE; NOTE 1
BL-WH
BL-WH
BL-WH
BL-WH
BL-WH
BL-WH
BL-WH
BL-WH
Note
1. When the circuit is in the automatic mode the RGB
drive is switched-on as soon as the black current loop
has stabilised. Under control of the µ-processor the
condition of the black current loop is indicated via the
BCF bit. When this bit changes to 0 the RGB drive can
be switched-on by setting the AST bit to 0.
1. For an equal delay of the luminance and chrominance
signal the delay must be set at a value of 160 ns. This
is only valid for a CVBS signal without group
delay distortions.
. The handbook can be ordered using the code 9398 510 63011.
“SNW-FQ-611E”
. The number of the quality specification can be found in the
“Quality Reference
Latch-up
At an ambient temperature of 70 °C nearly all pins meet the following specification:
• I
• I
≥ 100 mA or ≥1.5V
trigger
≤−100 mA or ≤−0.5V
trigger
DD(max)
DD(max)
.
Some pins have a slightly lower trigger current. The pin numbers and and the allowable trigger current are given below.
Pin 50: I
Pin 51: I
Pin 52: I
G.3.10control rangesee also Fig.8−80−dB
G.3.11suppression of output signal
when mute is active
G.3.12DC shift of the output when
mute is active
EXTERNAL AUDIO INPUT;(PIN 2)
G.4.1input signal amplitude (RMS
value)
G.4.2input resistance−25−kΩ
G.4.3voltage gain difference between
input and output
G.4.4crosstalk between internal and
external audio signals
AUTOMATIC VOLUME LEVELLING (ONLY IN TDA 8840/41/42/46/46A); CAPACITOR CONNECTED TO PIN 45; NOTE 21
G.5.1gain at maximum boost−6−dB
G.5.2gain at minimum boost−-14−dB
G.5.3charge (attack) current−1−mA
G.5.4discharge (decay) current−200−nA
G.5.5control voltage at maximum
C.4.16supply voltage (±10%)nominal controls−−tbfmV
C.4.17saturation (50 dB)nominal contrast−−tbfmV
C.4.18contrast (20 dB)nominal saturation−−tbfmV
C.4.19brightness (±0.5 V)nominal controls−−tbfmV
C.4.20temperature (range 40 °C)−−tbfmV
C.4.21signal-to-noise ratio of the
C.4.22CVBS input; note 5050−−dB
C.4.23residual voltage at the RGB
C.4.24at 2f
C.4.25bandwidth of output signalsRGB input; at −3dB9−−MHz
C.4.26CVBS input; at −3 dB;
C.4.27CVBS input; at −3 dB;
C.4.28S-VHS input; at −3dB6−−MHz
WHITE-POINT ADJUSTMENT
C.5.1I2C-bus setting for nominal gain HEX code−20H−
C.5.2adjustment range of RGB drive
2. This parameter is not tested during production and is just given as application information for the designer of the
television receiver.
3. Loop bandwidth BL = 60 kHz (natural frequency fN = 15 kHz; damping factor d = 2; calculated with top sync level as
FPLL input signal level).
4. The IF-PLL demodulator uses an internal VCO (no external LC-circuit required) which is calibrated by means of a
digital control circuit which uses the X-tal frequency of the colour decoder as a reference. The required IF frequency
for the various standards is set via the I2C-bus (IFA-IFC bits in sub-address 15H). When the system is locked the
resulting IF frequency is very accurate with a deviation from the nominal value of less than 25 kHz.
5. This parameter is not tested during production but is guaranteed by the design and qualified by means of matrix
batches which are made in the pilot production period.
6. Measured at 10 mV (RMS) top sync input signal.
7. So called projected zero point, i.e. with switched demodulator.
8. Measured in accordance with the test line given in Fig.14. For the differential phase test the peak white setting is
reduced to 87%.
The differential gain is expressed as a percentage of the difference in peak amplitudes between the largest and
smallest value relative to the subcarrier amplitude at blanking level.
The phase difference is defined as the difference in degrees between the largest and smallest phase angle.
9. This figure is valid for the complete video signal amplitude (peak white-to-black), see Fig.15.
10. The noise inverter is only active in the “strong signal mode” (no noise detected in the incoming signal)
11. The test set-up and input conditions are given in Fig.16. The figures are measured with an input signal of
10 mV RMS. The indicated parameter values are obtained when a capacitor with a value of 1 nF is connected in
parallel with the PLL loop filter on pin 5.
12. Measured at an input signal of 10 mV
voltage (RMS value). B = 5 MHz. Weighted in accordance with CCIR 567.
13. The AGC response time is also dependent on the acquisition time of the PLL demodulator. The values given are valid
when the PLL is in lock.
14. The AFC control voltage is generated by the digital tuning system of the PLL demodulator. This system uses the X-tal
frequency of the colour decoder as a reference and is therefore very accurate. For this reason no maximum and
minimum values are given for the window sensitivity figures (parameters M.7.2 and M.7.3). The tuning information is
supplied to the tuning system via the I2C-bus. 2 bits are reserved for this function. The AFC value is valid only when
the SL-bit is 1.
15. The ratio of the output signal amplitudes of the deemphasis pin (pin 55) and the audio output (pin 15) is dependent
on the type and/or the frequency of the X-tals connected to the IC (indicated via the XA/XB bits). The indicated values
are valid for the PAL, PAL/NTSC and multi-standard versions when a 4.43 MHz X-tal is connected to pin 35 (pin 51
in the QFP-64 envelope). For the NTSC types and the other IC’s (when only 3.5 MHz X-tals are used) the gain
between the deemphasis output and the audio output is a factor 2 higher so that the audio output signal is not effected
by the lower frequency deviation of the M/N standard.
, f = 5.5 MHz; FM: 1 kHz, +/- 17.5 kHz deviation. Measured with a bandwidth of 15 kHz and the audio
RMS
attenuator at -6 dB.
18. Vi = 100 mV
, f = 4.5 MHz, FM: 1 kHz, +/- 100 kHz deviation.
RMS
19. Unweighted RMS value, Vi = 100 mV
20. Audio attenuator at -20 dB; temperature range 10 to 50 °C.
21. The Automatic Volume Levelling (AVL) circuit stabilises automatically the audio output signal to a certain level which
can be set by means of the volume control. This AVL function prevents big audio output fluctuations due to variation
of the modulation depth of the transmitter. The AVL can be switched on and off via the I2C-bus.
For the TDA 8846/46A the AVL is active over an input voltage range (measured at the deemphasis output) between
75 and 750 mV
. For the TDA 8840/41/42 this input level is dependent on the X-tals which are connected to the
RMS
colour decoder. When only 3.5 MHz X-tals are connected (indicated via the XA/XB bits) the active input level is
identical to that of the TDA 8846/46A. When a 4.4 MHz X-tal is connected the input range is increased to 150 to 1500
mV
, this to cope with the larger FM swing of European transmitters.
RMS
The AVL control curve for the 2 standards is given in Fig.17 and Fig.18. The control range of +6 dB to −14 dB is valid
for input signals with 50% of the maximum frequency deviation.
22. Signal with negative-going sync. Amplitude includes sync pulse amplitude.
23. This parameter is measured at nominal settings of the various controls.
24. Indicated is a signal for a colour bar with 75% saturation (chroma : burst ratio = 2.2 : 1).
25. The saturation control is active on the internal signal (YUV) and on the second RGB input. The contrast control is
active on YUV and the 2 RGB inputs. Nominal contrast is specified with the DAC in position 20 HEX. Nominal
saturation as maximum -10 dB.
. The S/N is the ratio of black-to-white amplitude to the black level noise
26. Several versions have a YUV interface. The luminance and colour difference out- and inputs can directly be
connected. When additional picture improvement IC’s (like the TDA 9170) are applied the inputs of these IC’s must
be ac coupled because of the black level clamp requirement. The output signal of the picture improvement IC can
directly be coupled to the luminance and colour difference inputs as long as the dc level of these signals have a value
between 1 and 7 Volts (for the luminance signal) or between 1 and 4 Volts (for the UV signals). When the dc level of
the input signals exceed these levels the signals must be ac coupled and biased to a voltage level within these limits.
To be able to apply CTI IC’s like the TDA 4565/66 the gain of the luminance channel can be increased via the setting
of the GAI bit in the I2C subaddress 03.
27. When the decoder is forced to a fixed subcarrier frequency (via XA/XB or the CM-bits) the chroma trap is always
switched-on, also when no colour signal is identified. When 2 X-tals are active the chroma trap is switched-off when
no colour signal is identified.
28. Valid for a signal amplitude on the Y-input of 0.7 V black-to-white (100 IRE) with a rise time (10% to 90%) of 70 ns
and the video switch in the Y/C mode. During production the peaking function is not tested by measuring the
overshoots but by measuring the frequency response of the Y output.
29. For video signals with a black level which deviates from the back-porch blanking level the signal is “stretched” to the
blanking level. The amount of correction depends on the IRE value of the signal (see Fig.19). The black level is
detected by means of an internal capacitor. The black level stretcher can be switched on and off via the BKS bit in
the I2C-bus. The values given in the specification are valid only when the luminance input signal has an amplitude
of 1 V
30. The slicing level is independent of sync pulse amplitude. The given percentage is the distance between the slicing
level and the black level (back porch). When the amplitude of the sync pulse exceeds the value of 350 mV the sync
separator will slice the sync pulse at a level of 175 mV above top sync. The maximum sync pulse amplitude is 4 V
31. To obtain a good performance for both weak signal and VCR playback the time constant of the first control loop is
switched depending on the input signal condition and the condition of the I2C-bus. Therefore the circuit contains a
noise detector and the time constant is switched to ‘slow’ when too much noise is present in the signal. In the ‘fast’
mode during the vertical retrace time the phase detector current is increased 50% so that phase errors due to
head-switching of the VCR are corrected as soon as possible. Switching between the two modes can be
automatically or overruled by the I2C-bus.
The circuit contains a video identification circuit which is independent of first loop. This identification circuit can be
used to close or open the first control loop when a video signal is present or not present on the input. This enables
a stable On Screen Display (OSD) when just noise is present at the input. The coupling of the video identification
circuit with the first loop can be defeated via the I2C-bus.
To prevent that the horizontal synchronisation is disturbed by anti copy signals like Macrovision the phase detector
is gated during the vertical retrace period so that pulses during scan have no effect on the output voltage. The width
of the gate pulse is about 22 µs. During weak signal conditions (noise detector active) the gating is active during the
complete scan period and the width of the gate pulse is reduced to 5.7 µs so that the effect of noise is reduced to a
minimum.
The output current of the phase detector in the various conditions are shown in Table 75.
32. The IC’s have 2 protection inputs. The protection on pin 42 is intended to be used as “flash” protection. When this
protection is activated the horizontal drive is switched-off immediately and then switched-on again via the slow start
procedure.
The protection on pin 50 is intended for overvoltage (X-ray) protection. When this protection is activated the
horizontal drive can directly be switched-off (via the slow stop procedure). It is also possible to continue the horizontal
drive and to set the protection bit (XPR) in the output bytes of the I2C-bus. The choice between the 2 modes of
operation is made via the PRD bit.
33. During switch-on the horizontal output starts with the double frequency and with a duty cycle of 75% (VOUT = high).
After about 50 ms the frequency is changed to the normal value. Because of the high frequency the peak currents in
the horizontal output transistor are limited. Also during switch-off the frequency is switched to the double value and
the RGB drive is set to maximum so that the EHT capacitor is discharged. The switching to maximum drive occurs
only when RBL=0, for RBL=1 the drive voltage remains minimum during switch-off. After about 100 ms the RGB drive
is set to minimum and 50 ms later the horizontal drive is switched-off.
It is possible to discharge the EHT capacitor in the vertical overscan so that the screen stays black during switch-off.
This feature is activated by the OSO bit. In this condition the vertical scan is stopped and the current is set to the
maximum scan value. It should be checked with the picture tube supplier whether this mode of switch-off is allowed
for the given picture tube.
The horizontal output is gated with the flyback pulse so that the horizontal output transistor cannot be switched-on
during the flyback time.
34. The vertical blanking pulse in the RGB outputs has a width of 26 or 21 lines (50 or 60 Hz system). The vertical pulse
in the sandcastle pulse has a width of 14 lines. This to prevent a phase distortion on top of the picture due to a timing
modulation of the incoming flyback pulse.
35. The timing pulses for the vertical ramp generator are obtained from the horizontal oscillator via a divider circuit.
During TV reception this divider circuit has 3 modes of operation:
a) Search mode ‘large window’.
This mode is switched on when the circuit is not synchronized or when a non-standard signal (number of lines
per frame outside the range between 311 and 314(50 Hz mode) or between 261 and 264 (60 Hz mode) is
received). In the search mode the divider can be triggered between line 244 and line 361 (approximately
45 to 64.5 Hz).
b) Standard mode ‘narrow window’.
This mode is switched on when more than 15 succeeding vertical sync pulses are detected in the narrow window.
When the circuit is in the standard mode and a vertical sync pulse is missing the retrace of the vertical ramp
generator is started at the end of the window. Consequently, the disturbance of the picture is very small. The
circuit will switch back to the search window when, for 6 successive vertical periods, no sync pulses are found
within the window.
c) Standard TV-norm (divider ratio 525 (60 Hz) or 625 (50 Hz).
When the system is switched to the narrow window it is checked whether the incoming vertical sync pulses are
in accordance with the TV-norm. When 15 standard TV-norm pulses are counted the divider system is switched
to the standard divider ratio mode. In this mode the divider is always reset at the standard value even if the vertical
sync pulse is missing.
When 3 vertical sync pulses are missed the system switches back to the narrow window and when also in this
window no sync pulses are found (condition 3 missing pulses) the system switches over to the search window.
The vertical divider needs some waiting time during channel-switching of the tuner. When a fast reaction of the
divider is required during channel-switching the system can be forced to the search window by means of the NCIN bit
in subaddress 08.
When RGB signals are inserted the maximum vertical frequency is increased to 72 Hz. This has the consequence
that the circuit can also be synchronised by signals with a higher vertical frequency like VGA.
36. Conditions: frequency is 50 Hz; normal mode; VS = 1F.
37. During switch-off the RGB drive outputs are shortly set to maximum so that the EHT capacitor of the picture tube can
be discharged. The switch-off behaviour depends on the switch-off mode. When the vertical scan is set in the
overscan during switch-off the RGB outputs are first set to minimum during 20 ms, then the drive is set to maximum
during 80 ms followed by a period of 60 ms with the drive on minimum. When the vertical scan is active during
switch-off the RGB drive voltages are directly set to maximum when the switch-off command is given. The output
remain high during a period of 100 ms followed by a period of 60 ms with the drive on minimum.
38. The output range percentages mentioned for E-W control parameters are based on the assumption that 400 µA
variation in E-W output current is equivalent to 20% variation in picture width.
39. The IC’s have a zoom adjustment possibility for the horizontal and vertical deflection. For this reason an extra DAC
has been added in the vertical amplitude control which controls the vertical scan amplitude between 0.75 and 1.38
of the nominal scan. At an amplitude of 1.05 of the nominal scan the output current is limited and the blanking of the
RGB outputs is activated. This is illustrated in Fig.21. In addition to the variation of the vertical amplitude a vertical
scroll function is introduced so that it is always possible to display the most important part of the picture.
The nominal scan height must be adjusted at a position of 19 HEX of the vertical “zoom” DAC and 1F HEX of the
vertical scroll DAC.
40. At a chrominance input voltage of 660 mV (p-p) (colour bar with 75% saturation i.e. burst signal amplitude
300 mV (p-p)) the dynamic range of the ACC is +6 and −20 dB.
41. The ACL function can be activated by via the ACL bit in the I2C subaddress 19. The ACL circuit reduces the gain of
the chroma amplifier for input signals with a chroma-to-burst ratio which exceeds a value of 3.0.
42. All frequency variations are referenced to 3.58 or 4.43 MHz carrier frequency.
All oscillator specifications are measured with the Philips crystal series 9922 520 with a series capacitance of 18 pF.
The oscillator circuit is rather insensitive to the spurious responses of the X-tal. As long as the resonance resistance
of the third overtone is higher than that of the fundamental frequency the oscillator will operate at the right frequency.
The typical crystal parameters for the X-tals mentioned above are:
a) Load resonance frequency f0= 4.433619 or 3.579545 MHz; CL= 20 pF.
b) Motional capacitance CM= 20.5 fF (4.43 MHz crystal) or 14.5 fF (3.58 MHz crystal).
c) Parallel capacitance C0= 5.0 pf for both X-tals.
The minimum detuning range can only be specified if both the IC and the X-tal tolerances are known and therefore
the figures regarding catching range are only valid for the specified X-tal series. In this figure tolerances of the X-tal
with respect to the nominal frequency, motional capacitance and ageing have been taken into account and have
been counted for by gaussic addition.
Whenever different typical X-tal parameters are used the following equation might be helpful for calculating the
impact on the tuning capabilities:
Detuning range = CM /(1 + C0/CL)
The resulting detuning range should be corrected for temperature shift and supply voltage deviation of both the IC
and the X-tal. To guarantee a catching range of ±300 Hz on 4.43 MHz the minimum motional cpacitance of the X-tal
must have a value 13.2 fF or higher. For a catching range of 250 Hz with the 3.58 MHz X-tal the minimum motional
cpacitance must have a value of 9 fF.
The actual series capacitance in the application should be CL = 18 pF to account for parasitic capacitances on and
off chip.
For 3-norma applications with 2 X-tals connected to one pin the maximum parasitic capacitance of the X-tal pin
should not exceed 15 pF.
43. Because the base-band delay line is integrated the demodulated colour difference signals are matrixed before they
are supplied to the outputs. The colour difference out- and inputs must be dc coupled.
44. This parameter indicates the bandwidth of the complete chrominance circuit including the chrominance bandpass
filter. The bandwidth of the low-pass filter of the demodulator is approximately 1 MHz.
45. The subcarrier output signal can be used as reference signal for external comb filter IC’s (e.g. SAA 4961). When the
CMB bit is low the subcarrier signal is suppressed and the dc level is low. With the CMB bit high the output level is
high and the subcarrier signal is present.
46. The Dynamic Skin Tone Correction circuit is designed such that it corrects (instantaneously and locally) the hue of
those colours which are located in the area in the UV plane that matches to skin tones. The correction is dependent
on the luminance, saturation and distance to the preferred axis and can be realised for 2 different angles. This angle
can be set by means of the DSA bit. Because the amount of correction is dependent on the parameters of the
incoming YUV signal it is not possible to give exact figures for the correction angle. The correction angle of 45
(+/-22.5) degrees is just given as an indication and is valid for an input signal with a luminance signal amplitude of
75% and a colour saturation of 50%. A graphical representation of the control behaviour is given in Fig.20.
47. Because of the 2-point black current stabilisation circuit both the black level and the amplitude of the RGB output
signals depend on the drive characteristic of the picture tube. The system checks whether the returning measuring
currents meet the requirement and adapts the output level and gain of the circuit when necessary. Therefore the
typical value of the black level and amplitude at the output are just given as an indication for the design of the RGB
output stage.
The 2-point black level system adapts the drive voltage for each cathode in such a way that the 2 measuring currents
have the right value. This has the consequence that a change in the gain of the output stage will be compensated
by a gain change of the RGB control circuit. Because different picture tubes may require different drive voltage
amplitudes the ratio between the output signal amplitude and the inserted measuring pulses can be adapted via the
I2C-bus. This is indicated in the parameter “Adjustment range of the ratio between the amplitudes of the RGB drive
voltage and the measuring pulses”.
Because of the dependence of the output signal amplitude on the application the soft clipping limiting has been
related to the input signal amplitude.
48. For the alignment of the picture tube the vertical scan can be stopped by means of the VSD bit. In that condition a
certain black level is inserted at the RGB outputs. The value of this level can be adjusted by means of the brightness
control DAC.
49. When the reproduction of 4:3 pictures on a 16:9 picture tube is realised by means of a reduction of the horizontal
scan amplitude the edges of the picture may slightly be disturbed. This effect can be prevented by adding an
additional blanking to the RGB signals. The blanking pulse is derived form the horizontal oscillator and is directly
related to the incoming video signal (independent of the flyback pulse). The additional blanking overlaps the normal
blanking signal with about 1 µs on both sides. This blanking is activated with the HBL bit (only in the
TDA8843/44/47/54/57).
50. Signal-to-noise ratio (S/N) is specified as peak-to-peak signal with respect to RMS noise (bandwidth 5 MHz).
51. This is a current input.
52. The beam current limiting and the vertical guard function have been combined on this pin. The beam current limiting
function is active during the vertical scan period.
53. Via the “blue stretch” (BLS bit) or “extended blue stretch” (EBS bit) function the colour temperature of the bright
scenes (amplitudes which exceed a value of 80% of the nominal amplitude) can be increased. This effect is obtained
by decreasing the small signal gain of the red and green channel signals which exceed the 80% level. The effect is
illustrated in Fig.22.
In order to obtain correct tracking of the vertical and
horizontal EHT-correction, the EW output stage should be
dimensioned as illustrated in Fig.24.
Resistor REW determines the gain of the EW output stage.
Resistor Rc determines the reference current for both the
vertical sawtooth generator and the geometry processor.
The preferred value of Rc is 39 kΩ which results in a
reference current of 100 µA (V
The deflection processor of the TDA8840/41/42/46/46A
offers 5 control parameters for picture alignment, viz:
• S-correction
• vertical amplitude
• vertical slope
• vertical shift
• horizontal shift.
The TDA 8843/44/47/54H/57H offer in addition:
• EW width
• EW parabola width
• EW corner parabola
• EW trapezium correction.
• vertical zoom
• vertical scroll
It is important to notice that the IC’s are designed for use
with a DC-coupled vertical deflection stage. This is the
reason why a vertical linearity alignment is not necessary
(and therefore not available).
For a particular combination of picture tube type, vertical
output stage and EW output stage it is determined which
are the required values for the settings of S-correction, EW
parabola/width ratio and EW corner/parabola ratio. These
parameters can be preset via the I2C-bus, and do not need
any additional adjustment. The rest of the parameters are
preset with the mid-value of their control range (i.e. 1FH),
or with the values obtained by previous TV-set
adjustments.
The vertical shift control is meant for compensation of
off-sets in the external vertical output stage or in the
picture tube. It can be shown that without compensation
these off-sets will result in a certain linearity error,
especially with picture tubes that need large S-correction.
The total linearity error is in first order approximation
proportional to the value of the off-set, and to the square of
the S-correction needed. The necessity to use the vertical
shift alignment depends on the expected off-sets in vertical
output stage and picture tube, on the required value of the
S-correction, and on the demands upon vertical linearity.
TDA884X/5X-N2 series
For adjustment of the vertical shift and vertical slope
independent of each other, a special service blanking
mode can be entered by setting the SBL bit HIGH. In this
mode the RGB-outputs are blanked during the second half
of the picture. There are 2 different methods for alignment
of the picture in vertical direction. Both methods make use
of the service blanking mode.
The first method is recommended for picture tubes that
have a marking for the middle of the screen. With the
vertical shift control the last line of the visible picture is
positioned exactly in the middle of the screen. After this
adjustment the vertical shift should not be changed. The
top of the picture is placed by adjustment of the vertical
amplitude, and the bottom by adjustment of the vertical
slope.
The second method is recommended for picture tubes that
have no marking for the middle of the screen. For this
method a video signal is required in which the middle of the
picture is indicated (e.g. the white line in the circle test
pattern). With the vertical slope control the beginning of the
blanking is positioned exactly on the middle of the picture.
Then the top and bottom of the picture are placed
symmetrical with respect to the middle of the screen by
adjustment of the vertical amplitude and vertical shift.
After this adjustment the vertical shift has the right setting
and should not be changed.
If the vertical shift alignment is not required VSH should be
set to its mid-value (i.e. VSH = 1F). Then the top of the
picture is placed by adjustment of the vertical amplitude
and the bottom by adjustment of the vertical slope. After
the vertical picture alignment the picture is positioned in
the horizontal direction by adjustment of the EW width and
the horizontal shift. Finally (if necessary) the left- and
right-hand sides of the picture are aligned in parallel by
adjusting the EW trapezium control.
To obtain the full range of the vertical zoom function with
the TDA 8844/47/54H/57H the adjustment of the vertical
geometry should be carried out at a nominal setting of the
zoom DAC at position 19 HEX and the vertical scroll DAC
at position 1F HEX.
BY DIP OR WAVE
The maximum permissible temperature of the solder is
260 °C; this temperature must not be in contact with the
joint for more than 5 s. The total contact time of successive
solder waves must not exceed 5 s.
The device may be mounted up to the seating plane, but
the temperature of the plastic body must not exceed the
specified storage maximum. If the printed-circuit board has
been pre-heated, forced cooling may be necessary
immediately after soldering to keep the temperature within
the permissible limit.
REPAIRING SOLDERED JOINTS
Apply a low voltage soldering iron below the seating plane
(or not more than 2 mm above it). If its temperature is
below 300 °C, it must not be in contact for more than 10 s;
if between 300 and 400 °C, for not more than 5 s.
Plastic quad flat-packs
B
YWAVE
During placement and before soldering, the component
must be fixed with a droplet of adhesive. After curing the
adhesive, the component can be soldered. The adhesive
can be applied by screen printing, pin transfer or syringe
dispensing.
Maximum permissible solder temperature is 260 °C, and
maximum duration of package immersion in solder bath is
10 s, if allowed to cool to less than 150 °C within 6 s.
Typical dwell time is 4 s at 250 °C.
TDA884X/5X-N2 series
A modified wave soldering technique is recommended
using two solder waves (dual-wave), in which a turbulent
wave with high upward pressure is followed by a smooth
laminar wave. Using a mildly-activated flux eliminates the
need for removal of corrosive residues in most
applications.
Y SOLDER PASTE REFLOW
B
Reflow soldering requires the solder paste (a suspension
of fine solder particles, flux and binding agent) to be
applied to the substrate by screen printing, stencilling or
pressure-syringe dispensing before device placement.
Several techniques exist for reflowing; for example,
thermal conduction by heated belt, infrared, and
vapour-phase reflow. Dwell times vary between 50 and
300 s according to method. Typical reflow temperatures
range from 215 to 250 °C.
Preheating is necessary to dry the paste and evaporate
the binding agent. Preheating duration: 45 min at 45 °C.
REPAIRING SOLDERED JOINTS (BY HAND-HELD SOLDERING
IRON OR PULSE
Fix the component by first soldering two, diagonally
opposite, end pins. Apply the heating tool to the flat part of
the pin only. Contact time must be limited to 10 s at up to
300 °C. When using proper tools, all other pins can be
soldered in one operation within 2 to 5 s at between 270
and 320 °C. (Pulse-heated soldering is not recommended
for SO packages.)
For pulse-heated solder tool (resistance) soldering of VSO
packages, solder is applied to the substrate by dipping or
by an extra thick tin/lead plating before package
placement.
Objective specificationThis data sheet contains target or goal specifications for product development.
Preliminary specificationThis data sheet contains preliminary data; supplementary data may be published later.
Product specificationThis data sheet contains final product specifications.
Limiting values
Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 134). Stress above one or
more of the limiting values may cause permanent damage to the device. These are stress ratings only and operation
of the device at these or at any other conditions above those given in the Characteristics sections of the specification
is not implied. Exposure to limiting values for extended periods may affect device reliability.
Application information
Where application information is given, it is advisory and does not form part of the specification.
LIFE SUPPORT APPLICATIONS
These products are not designed for use in life support appliances, devices, or systems where malfunction of these
products can reasonably be expected to result in personal injury. Philips customers using or selling these products for
use in such applications do so at their own risk and agree to fully indemnify Philips for any damages resulting from such
improper use or sale.
PURCHASE OF PHILIPS I
Purchase of Philips I
components in the I2C system provided the system conforms to the I2C specification defined by
Philips. This specification can be ordered using the code 9398 393 40011.
2
C COMPONENTS
2
C components conveys a license under the Philips’ I2C patent to use the
December 16, 199767
Page 68
Philips Semiconductors – a worldwide company
Argentina: see South America
Australia: 34 Waterloo Road, NORTH RYDE, NSW 2113,
United States: 811 East Arques Avenue, SUNNYVALE, CA 94088-3409,
Tel. +1 800 234 7381
Uruguay: see South America
Vietnam: see Singapore
Yugoslavia: PHILIPS, Trg N. Pasica 5/v, 11000 BEOGRAD,
Tel. +381 11 625 344, Fax.+381 11 635 777
For all other countries apply to: Philips Semiconductors, Marketing & Sales Communications,
Building BE-p, P.O. Box 218, 5600 MD EINDHOVEN, The Netherlands, Fax. +31 40 27 24825
The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed
without notice. No liability will be accepted by the publisher for any consequence of its use. Publication thereof does not convey nor imply any license
under patent- or other industrial or intellectual property rights.
Printed in The Netherlands
Internet: http://www.semiconductors.philips.com
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