Vestel 11AK33 Service Manual
11 AK-33
Service Manual
1. INTRODUCTION ________________________________________________4
2. SMALL SIGNAL PART WITH TDA8885 _____________________________4
2.1. Vision IF amplifier _________________________________________________ 4
2.2. Video Switches_____________________________________________________ 5
2.3. Sound Circuit______________________________________________________ 5
2.4. Synchronisation circuit______________________________________________5
2.5. Chroma and Luminance processing ___________________________________ 6
2.6. Colour Decoder ____________________________________________________ 6
2.7. PICTURE IMPROVEMENT FEATURES______________________________ 7
2.8. RGB output circuit and black-current stabilisation_______________________ 7
2.9. EAST – WEST OUTPUT STAGE_____________________________________ 8
3. TUNER_________________________________________________________8
4. VIDEO SWITCH TEA6415C _______________________________________9
5. MULTI STANDARD SOUND PROCESSOR___________________________9
6. SOUND OUTPUT STAGE WITH TDA 7265___________________________9
7. VERTICAL OUTPUT STAGE WITH STV 9379 _______________________10
8. VIDEO OUTPUT AMPLIFIER TDA6108____________________________10
9. COMBFILTER TDA 9181_________________________________________10
10. POWER SUPPLY (SMPS) _______________________________________10
11. POWER FACTOR CORRECTION ________________________________10
12. MICROCONTROLLER SDA555X ________________________________10
12.1. General Features ________________________________________________ 10
12.2. External Crystal and Programmable clock speed______________________ 10
12.3. Microcontroller Features _________________________________________10
12.4. Memory _______________________________________________________ 11
12.5. Display Features ________________________________________________ 11
12.6. ROM Characters ________________________________________________ 11
12.7. Acquisition Features _____________________________________________ 11
12.8. Ports __________________________________________________________ 11
13. SERIAL ACCESS CMOS 8K (1024*8) EEPROM ST24C08 ____________12
14. CLASS AB STEREO HEADPHONE DRIVER TDA1308 ______________12
15. SAW FILTERS________________________________________________12
16. IC DESCRIPTIONS AND INTERNAL BLOCK DIAGRAM____________12
16.1. TDA8885:______________________________________________________ 12
16.1.1. GENERAL DESCRIPTION _____________________________________________12
16.1.2. FEATURES__________________________________________________________12
16.1.3. Pin Description _______________________________________________________13
16.2. UV1315, UV1316 ________________________________________________ 15
16.2.1. General description of UV1315: __________________________________________15
16.2.2. Features of UV1315:___________________________________________________15
16.2.3. General description of UV1316: __________________________________________15
16.2.4. Features of UV1316:___________________________________________________15
16.3. TEA6415C:_____________________________________________________ 16
16.3.1. General Description: ___________________________________________________16
16.3.2. Features: ____________________________________________________________16
16.4. TDA7265:______________________________________________________ 17
16.4.1. Features: ____________________________________________________________17
16.4.2. Pinning:_____________________________________________________________17
16.5. TDA6108Q: ____________________________________________________ 17
16.5.1. Features: ____________________________________________________________17
16.6. 74 HCT 32 _____________________________________________________ 18
16.6.1. PINNING ___________________________________________________________18
16.7. MC44608 ______________________________________________________ 18
16.7.1. General description:____________________________________________________18
16.7.2. General Features ______________________________________________________18
16.8. SDA5555: ______________________________________________________ 19
16.8.1. General description:____________________________________________________19
16.9. TDA9181:______________________________________________________ 20
16.9.1. General Features:______________________________________________________20
16.9.2. Limits:______________________________________________________________20
16.10. TCD1102:______________________________________________________ 21
16.10.1. Description ________________________________________________________21
16.10.2. Applications _______________________________________________________21
16.10.3. General features: ____________________________________________________21
16.11. ST24C08: ______________________________________________________ 21
16.11.1. General description:__________________________________________________21
16.11.2. Features: __________________________________________________________21
16.12. TDA1308:______________________________________________________ 22
16.12.1. Features: __________________________________________________________22
16.13. PCF8583: ______________________________________________________ 22
16.13.1. FEATURES________________________________________________________22
16.13.2. GENERAL DESCRIPTION ___________________________________________23
16.14. MC33260:______________________________________________________ 23
16.14.1. General Features:____________________________________________________23
16.14.2. Safety Features:_____________________________________________________23
16.14.3. LIMITS:___________________________________________________________23
16.14.4. PINNING _________________________________________________________23
16.15. STV9379: ______________________________________________________ 24
16.15.1. DESCRIPTION_____________________________________________________24
16.15.2. PINNING _________________________________________________________24
16.16. MSP34XX :_____________________________________________________24
MSP3410D ________________________________________________________24
16.17. LM358N: ______________________________________________________ 26
16.17.1. General Description__________________________________________________26
16.17.2. Unique Characteristics________________________________________________26
16.17.3. Advantages ________________________________________________________26
16.17.4. Features___________________________________________________________26
17. AK33 CHASSIS MANUAL ADJUSTMENTS PROCEDURE ___________26
1. INTRODUCTION
11AK33 is a 110ø chassis capable of driving 28-29”,32”,33” tubes at appropriate currents The chassis is a
Frequency Controlled Tuning (PLL) and control system for multi-standard TV receivers with onscreen-display (OSD) for all relevant control functions. The system is based on the ‘one-chip’ I2C bus
controlled video processing / deflection IC TDA8885 which also controls sound.
German stereo and Nicam is detected and processed by the MSP 3410 G. Dolby sound is processed by
MSP 3452 G, virtual dolby by MSP 3411G, BTSC Stereo by MSP 3430G IC’s by option. All sound
processors also control the sound volume, balance, tone and spatial stereo effect.
The user-interface is menu based control system with cursor keys. Only for some functions the colour
keys are needed: This means that some of the functions can also be operated from the local keyboard
(i.e. Vol -, Vol +, P -, P+ and M).
Teletext is done by the microcontroller on-chip teletext module.
2. SMALL SIGNAL PART WITH TDA8885
The TDA8885 combine all small signal functions required for a colour TV receiver.
2.1. Vision IF amplifier
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. 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 clock frequency of the m-Controller/Teletext 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 2 C-bus. To get a good 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 I 2 C 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 AGC-detector operates on top sync and top white-level. The demodulation polarity is switched
via the I 2 C-bus. The AGC detector capacitor is integrated. The time-constant can be chosen via the I 2
C-bus. The time-constant of the AGC system during positive modulation is rather long to avoid visible
variations 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 circuit contains 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 use
both Ident outputs to obtain a reliable search system. The Ident output is supplied to the tuning system
via the I 2 C-bus. The input of the identification circuit is connected to pin 24, the internal CVBS input.
This has the advantage that the Ident circuit can also be made operative when a scrambled signal is
received (descrambler connected between the IF video output (pin 16) and pin 24). A second advantage
is that the Ident circuit can be used when the IF amplifier is not used 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 IC contains a group delay correction circuit, which can be switched between the
BG and a flat group delay response characteristic. This has the advantage that in multi-standard
receivers no compromise has to be made for the choice of the SAW filter. Also the sound trap is
integrated within the IC .The centre frequency of the trap can be switched via the I 2 C-bus. For monoFM versions it is possible to obtain a demodulated IF video signal which has not passed the sound trap
so that an external stereo decoder can be driven. This function is selected by means of the ICO bit (subaddress 28H). The signal is available on pin 27 (audio output pin when ICO = 0). The S/N ratio of the
selected video signal can be read via the bits SN1/SN0 in sub-address 03H.
2.2. Video Switches
The circuit has an input for the internal CVBS signal and 2 inputs for external CVBS or Y signals. The
circuit has only 1 chroma input so that it is not possible to apply 2 separate Y/C inputs. The switch
configuration is given in Fig. A. The selection of the various sources is made via the I 2 C-bus. The
QFP-64 version has 2 independently switchable outputs. The CVBS1O output is identical to the
selected signal that is supplied to the internal video processing circuit and can therefore be used as
source signal for a teletext decoder. Both CVBS outputs have an amplitude of 2.0 VP-P . The CVBS2O
output can for instance be used as drive signal for a PIP decoder. If the Y/C-3 signal is selected for one
of the outputs the luminance and chrominance signals are added so that a CVBS signal is obtained
again.
2.3. Sound Circuit
The sound IF amplifier is similar to the vision IF amplifier and has a gain control range of about 66 dB.
The AGC circuit is related to the SIF carrier levels (average level of AM or FM carriers) and ensures a
constant signal amplitude of the AM demodulator and the QSS mixer. A multiplier realises the single
reference QSS mixer. In this multiplier the SIF signal is converted to the intercarrier frequency by
mixing it with the regenerated picture carrier from the VCO. The mixer output signal is supplied to the
output via a high-pass filter for attenuation of the residual video signals. With this system a high
performance hi-fi stereo sound processing can be achieved. To optimise the performance of the
demodulator the offset can be compensated by means of an I 2 C-bus setting. The AM sound
demodulator is realised by a multiplier. The modulated sound IF signal is multiplied in phase with the
limited SIF signal. The demodulator output signal is supplied to the output via a low-pass filter for
attenuation of the carrier harmonics. The AM signal is supplied to the output (pin 27) via the volume
control. It is possible to get the AM output signal (not controlled on amplitude) on the QSS intercarrier
output. The selection is made by means of the AM bit in sub-address 29H. Another possibility is that
pin 11 can be used as external audio input pin and pin 49 can be used as (non-controlled) AM output
pin. This can be realised by means of the setting the control bits CMB0 and CMB1 in sub-address 22H.
2.4. 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 whether the line oscillator is synchronised with the incoming
signal 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 statically steepness so that the phase of
the picture is independent of the line frequency. The horizontal drive signal is generated by an internal
VCO, which is running at a frequency of 25 MHz. This oscillator is stabilised to that frequency by
using the 12 MHz frequency of the crystal oscillator as a reference. The time-constant of the first loop
can be forced by the I 2 C-bus (fast or slow). If required the IC can select the time-constant depending
on the noise content of the incoming video signal. The horizontal output signal is generated by means
of a second loop, which compares the phase of the internal oscillator signal with the phase of the
incoming flyback pulse. The time-constant of this loop is connected externally and can be used as input
for a dynamic horizontal phase correction. To obtain a smooth switch-on and switch-off behaviour of
the horizontal output stage the horizontal drive signal is switched-on and off via the soft-start/soft-stop
procedure. This function is realised by means of a variation of the TON of the horizontal drive pulse.
When the soft-start procedure is completed the horizontal output is gated with the flyback pulse so that
the horizontal output transistor cannot be switched-on during the flyback time. An additional function
of the IC is the ‘low-power start-up’ feature. For this function a supply voltage with a value between 3
and 5 V must be available at the start-up pin (required current 5 mA typical). When all sub-address
bytes have been sent and the POR and XPR flags have been cleared, the horizontal output can be
switched-on via the STB-bit (sub-address 24H). In this condition the horizontal drive signal has the
nominal TOFF and the TON grows gradually from zero to the nominal value as indicated in the softstart behaviour. As soon as the 8 V supply is present the switch-on procedure (e.g. closing of the
second loop) is continued. The presence of the 8 V supply voltage is indicated by the SUP bit in the I 2
C-bus output byte 02. The circuit generates a vertical sync pulse. This pulse can be selected on pin 49
via the bits CMB1 and CMB0. In the 100 Hz input processor versions the vertical sync pulse is
available on pin 63 and the horizontal pulse on pin 56. Via the I C-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. 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 I 2 C-bus output bytes. The choice is made via the input bit PRD. When PRD
= 1 and an overvoltage is detected the drive is switched-off and the STB bit is set to 0. Switching on of
the drive is only possible when the XPR flag is cleared. The IC has a second protection input on the j2
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 is 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 I 2 C-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 I 2 C bus.
2.5. Chroma and Luminance processing
The circuit contains 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 reference
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 I 2 C-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.
2.6. Colour Decoder
The colour decoder can decode PAL, NTSC and SECAM signals. The internal clock signals for the
various colour standards are generated by means of an internal VCO, which uses the 12 MHz crystal
frequency as a reference. 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 subaddress 21H. The IC contains an
Automatic Colour Limiting (ACL) circuit which is switchable via the I 2 C-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 autocalibrating PLL demodulator which has two references, viz: the divided 12 MHz reference frequency
of the crystal 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. The
reference frequency of the colour decoder is fed to the Fsc output (pin 49) and can be used to tune an
external comb filter. The base-band delay line is integrated. 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.
2.7. PICTURE IMPROVEMENT FEATURES
In the TDA 8885 series various picture improvement features have been integrated. These features are:
-Video dependent coring in the peaking circuit. The coring can be activated only in the low-light parts
of the screen. This effectively reduces noise while having maximum peaking in the bright parts of the
picture.
-Colour Transient Improvement (CTI). This circuit improves the rise and fall times of the colour
difference signals. The function is realised by using delay cells with a length of 300 ns.
-Black-stretch. This circuit corrects the black level for incoming video signals, which have a deviation
between the black level and the blanking, level (back porch). The time constant for the black stretcher
is realised internally
-Blue-stretch. This circuit is intended to shift colour near ‘white’ with sufficient contrast values
towards more blue to obtain a brighter impression of the picture
-White-stretch. This function adapts the transfer characteristic of the luminance amplifier in a nonlinear way dependent on the picture content. The system operates such that maximum stretching is
obtained when signals with a low video level are received. For bright pictures the stretching is not
active.
-Dynamic skin tone (flesh) control. This function is realised in the YUV domain by detecting the
colourss near to the skin tone. The correction angle can be controlled via the I2 C-bus.
2.8. RGB output circuit and black-current stabilisation
The ICs have a very flexible control circuit for RGB and YUV input signals, which has the following
features:
· Input which can be used for YUV or RGB input signals and as YUV interface. The selection of the
various modes can be realised via the I2 C-bus. For the YUV input 2 different input signal conditions
can be chosen. It is also possible to connect the synchronisation circuit to the incoming Y input signal.
This input signal can be controlled on saturation, contrast and brightness.
· The RGB-1 input which is intended for OSD/text signals and which can be controlled on contrast and
brightness. 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. It is also possible to convert the incoming
RGB-1 signal to a YUV signal. The resulting signal is supplied to the YUV outputs.
· The TDA 888X versions have an additional YUV or RGB input which can be controlled on contrast,
saturation and brightness. The various input signal conditions are given. 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. The control circuit has a half tone input, which can be used to reduce the
contrast setting during mixed mode operation for teletext and OSD signals. The output signal has
amplitude of about 2 V 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 38). This blanking action at the
RGB outputs has some delay, which must be compensated externally.
To obtain an accurate biasing of the picture tube the ‘Continuous Cathode Calibration’ system has been
included in this IC. Via the I2 C-bus a black level offset can be made with respect to the level which is
generated by the black current stabilisation system. In this way different colour temperatures can be
obtained for the bright and the dark part of the picture.
The black current stabilisation system checks the output level of the 3 channels and indicates whether
the black level of the highest output is in a certain window (WBC-bit) or below or above this window
(HBC-bit). This indication can be read from the I2 C-bus and can be used for automatic adjustment of
the Vg2 voltage during the production of the TV receiver.
The control circuit contains a beam current limiting circuit and a peak white limiting circuit. The peak
white level is adjustable via the I2 C-bus. To prevent that the peak white limiting circuit reacts on the
high frequency content of the video signal a low-pass filter is inserted in front of the peak detector. The
circuit also contains a soft-clipper, which prevents that the high frequency peaks in the output signal
become too high. The difference between the peak white limiting level and the soft clipping level is
adjustable via the I2 C-bus in a few steps.
During switch-off of the TV receiver, the black current control circuit generates a fixed beam current.
This current ensures that the picture tube capacitance is discharged. During the switch-off period the
vertical deflection can be placed in an overseen position so that the discharge is not visible on the
screen.
2.9. EAST – WEST OUTPUT STAGE
In order to obtain correct tracking of the vertical and horizontal EHT-correction, the EW output stage
should be dimensioned as illustrated in Figure. 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 kW which results in a reference current of 100 mA
(Vref = 3.9 V).
The value of REW must be:
REW = RC * ( V
/ (18* V
scan
ref
) )
Example: With Vref = 3.9 V; Rc =39 kohm and Vscan = 120 V then REW =68 kohm
3. TUNER
PLL tuner is used as a tuner.
UV1316 (VHF/UHF) is used as a PLL tuner. For only PALM/N, NTSC M applications UV 1336 are used as the
PLL tuner.
Channel coverage of UV1316:
OFF-AIR CHANNELS CABLE CHANNELS
BAND
FREQUENCY
RANGE (MHz)
Low Band E2 to C 48.25 to 82.25 (1) S01 to S08
69.25 to 154.25
CHANNELS FREQUENCY CHANNELS
RANGE (MHz)
Mid Band E5 to E12 175.25 to 224.25 S09 to S38
161.25 to 439.25
High Band E21 to E69 471.25 to 855.25 (2) S39 to S41
447.25 to 463.25
(1). Enough margin is available to tune down to 45.25 MHz.
(2). Enough margin is available to tune up to 863.25 MHz.
Noise Typical Max. Gain Min. Typical
Low band : 5dB 9dB All channels : 38dB 44dB
Mid band : 5dB 9dB Gain Taper (of-air channels) : - -
High band : 6dB 9dB
Channel Coverage UV1336:
BAND CHANNELS FREQUENCY
Low Band 2 to D 55.25 to 139.25
Mid Band E to PP 145.25 to 391.25
High Band QQ to 69 397.25 to 801.25
Noise is typically 6dB for all channels. Gain is minimum 38dB and maximum 50dB for all channels.
4. VIDEO SWITCH TEA6415C
In case of three or more external sources are used, the video switch IC TEA6415C is used. The main function of
this device is to switch 8 video-input sources on the 6 outputs.
Each output can be switched on only one of each input. On each input an alignment of the lowest level of the
signal is made (bottom of sync. top for CVBS or black level for RGB signals).
Each nominal gain between any input and output is 6.5dB.For D2MAC or Chroma signal the alignment is
switched off by forcing, with an external resistor bridge, 5VDC on the input. Each input can be used as a normal
input or as a MAC or Chroma input (with external Resistor Bridge). All the switching possibilities are changed
through the BUS.
Driving 75ohm load needs an external resistor.
It is possible to have the same input connected to several outputs.
Max.
52dB
8dB
RANGE (MHz)
5. MULTI STANDARD SOUND PROCESSOR
The MSP 34x0D is designed to perform demodulation of FM or AM-Mono TV sound. Alternatively, two-carrier
FM systems according to the German or Korean terrestrial specs or the satellite specs can be processed with the
MSP 34x0D. Digital demodulation and decoding of NICAM-coded TV stereo sound, is done only by the MSP
3410. The MSP 34x0D offers a powerful feature to calculate the carrier field strength which can be used for
automatic standard detection (terrestrial) and search algorithms (satellite).
6. SOUND OUTPUT STAGE WITH TDA 7265
TDA7265 is a class AB dual Audio power amplifier assembled in the multiwatt package.
Mute stand-by function of the audio amplifier can be described as the following; the pin 5
(MUTE/STAND-BY) controls the amplifier status by two different thresholds, referred to +Vs. When
Vpin (5) higher than (+Vs - 2.5V) the amplifier is in Stand-by mode and the final stage generators are
off. When Vpin (5) is between (+Vs – 2.5V) and (+Vs – 6V) the final stage current generators are
switched on and the amplifier is in mute mode. When the Vpin (5) is lower than +Vs – 6V the amplifier
is play mode.
7. VERTICAL OUTPUT STAGE WITH STV 9379
The IC TDA9379FA is the vertical deflection booster circuit. Two supply voltages, +12V and –12V are
needed to scan the inputs VERT+ and VERT-, respectively. And a third supply voltage, +45V for the
flyback limiting are needed. The vertical deflection coil is connected in series between the output and
feedback to the input.
8. VIDEO OUTPUT AMPLIFIER TDA6108
The TDA6107/08Q includes three video output amplifiers in a SIL 9 MP (Single in Line 9 pins Medium Power)
package SOT111BE, using high-voltage DMOS technology, and is intended to drive the three cathodes of a colour
picture tube.
In contrast to previous types of DMOS video amplifiers, all external resistors (Rf, Ri and Ra) are integrated, so the
gain is fixed.
To obtain maximum performance, the amplifier should be used with black-current control and mounted on the
CRT panel.
9. COMBFILTER TDA 9181
The TDA 9181 is an adaptive PAL/NTSC comb filter with two internal delay lines, filters, clock
control, and input clamps. Video standards PAL B, G, H, I, M and N NTSC M are supported.
Two CVBS input signals can be selected by means of input switch.
In addition to the comb filter the circuit contains an output switch so that a selection can be made between the
combed CVBS signal and an external Y/C signal.
The supply voltage is 5V.
10. POWER SUPPLY (SMPS)
The DC voltages required at various parts of the chassis are provided by an SMPS transformer controlled by the IC
MC44608, which is designed for driving, controlling and protecting switching transistor of SMPS. The transformer
produces 150V for FBT input, ?14V for audio output IC, S+3.3, S+5V and 8V for TDA8885.
11. POWER FACTOR CORRECTION
The MC33260 is a controller for Power Factor Correction pre-converters meeting international
standard requirements in electronic ballast and off–line power conversion applications. Designed to
drive a free frequency discontinuous mode, it can also be synchronised and in any case, it features very
effective protections that ensure a safe and reliable operation.
12. MICROCONTROLLER SDA555X
12.1. General Features
• Feature selection via special function register
• Simultaneous reception of TTX, VPS, PDC, and WSS (line 23)
• Supply Voltage 2.5 and 3.3 V
• ROM version package P-SDIP 52
• ROMless version package P-LCC84
12.2. External Crystal and Programmable clock speed
• Single external 6MHz crystal, all necessary clocks are generated internally
• CPU clock speed selectable via special function registers.
• Normal Mode 33.33 MHz CPU clock, Power Save mode 8.33 MHz
12.3. Microcontroller Features
• 8bit 8051 instruction set compatible CPU.
• 33.33-MHz internal clock (max.)
• 0.360 ms (min.) instruction cycle
• Two 16-bit timers
• Watchdog timer
• Capture compare timer for infrared remote control decoding
• Pulse width modulation unit (2 channels 14 bit, 6 channels 8 bit)
• ADC (4 channels, 8 bit)
• UART
12.4. Memory
• Non-multiplexed 8-bit data and 16 … 20-bit address bus (ROMless Version)
• Memory banking up to 1Mbyte (ROMless version)
• Up to 128 Kilobyte on Chip Program ROM
• Eight 16-bit data pointer registers (DPTR)
• 256-bytes on-chip Processor Internal RAM (IRAM)
• 128bytes extended stack memory.
• Display RAM and TXT/VPS/PDC/WSS-Acquisition-Buffer directly accessible via MOVX
• UP to 16KByte on Chip Extended RAM (XRAM) consisting of;
- 1 Kilobyte on-chip ACQ-buffer-RAM (access via MOVX)
- 1 Kilobyte on-chip extended-RAM (XRAM, access via MOVX) for user software
- 3 Kilobyte Display Memory
12.5. Display Features
• ROM Character set supports all East and West European Languages in single device
• Mosaic Graphic Character Set
• Parallel Display Attributes
• Single/Double Width/Height of Characters
• Variable Flash Rate
• Programmable Screen Size (25 Rows x 33...64 Columns)
• Flexible Character Matrixes (HxV) 12 x 9...16
• Up to 256 Dynamical Redefinable Characters in standard mode; 1024 Dynamical
Redefinable Characters in Enhanced Mode
• CLUT with up to 4096 colour combinations
• Up to 16 Colours per DRCS Character
• One out of Eight Colours for Foreground and Background Colours for 1-bit DRCS and
12.6. ROM Characters
• Shadowing
• Contrast Reduction
• Pixel by Pixel Shiftable Cursor With up to 4 Different Colours
• Support of Progressive Scan and 100 Hz.
• 3 X 4Bits RGB-DACs On-Chip
• Free Programmable Pixel Clock from 10 MHz to 32MHz
• Pixel Clock Independent from CPU Clock
• Multinorm H/V-Display Synchronisation in Master or Slave Mode
12.7. Acquisition Features
• Multistandard Digital Data Slicer
• Parallel Multi-norm Slicing (TTX, VPS, WSS, CC, G+)
• Four Different Framing Codes Available
• Data Caption only limited by available Memory
• Programmable VBI-buffer
• Full Channel Data Slicing Supported
• Fully Digital Signal Processing
• Noise Measurement and Controlled Noise Compensation
• Attenuation Measurement and Compensation
• Group Delay Measurement and Compensation
• Exact Decoding of Echo Disturbed Signals
12.8. Ports
• One 8-bit I/O-port with open drain output and optional I 2 C Bus emulation support (Port0)
• Two 8-bit multifunction I/O-ports (Port1, Port3)
• One 4-bit port working as digital or analogue inputs for the ADC (Port2)
• One 2-bit I/O port with secondary functions (P4.2, 4.3, 4.7)
• One 4-bit I/O-port with secondary function (P4.0, 4.1, 4.4) (Not available in P-SDIP 52)
13. SERIAL ACCESS CMOS 8K (1024*8) EEPROM ST24C08
The ST24C08 is a 8Kbit electrically erasable programmable memory (EEPROM), organised as 4 blocks of 256*8
bits.
The memory is compatible with the I²C standard, two wire serial interface, which uses a bi-directional data bus and
serial clock.
The memory carries a built-in 4 bit, unique device identification code (1010) corresponding to the I²C bus
definition.
This is used together with 1 chip enable input (E) so that up to 2*8K devices may be attached to the I²C bus and
selected individually.
14. CLASS AB STEREO HEADPHONE DRIVER TDA1308
The TDA1308 is an integrated class AB stereo headphone driver contained in a DIP8 plastic package.
The device is fabricated in a 1 mm CMOS process and has been primarily developed for portable digital audio
applications.
15. SAW FILTERS
Saw filter type : Model:
K9356M : PAL-SECAM B/G/D/K/I STEREO (AUDIO IF)
K9656M : PAL-SECAM B/G/D/K/I/L/L’ STEREO (AUDIO IF)
K3958M : PAL-SECAM B/G/D/K/I/L/L’ STEREO (VIDEO IF)
16. IC DESCRIPTIONS AND INTERNAL BLOCK DIAGRAM
? TDA8885
? TUNER (UV1315, UV1316)
? TEA6415C
? TDA 7265
? TDA6108Q
? 74HCT32
? MC44608
? SDA5555
? TDA9181
? TCD1102
? ST24C08
? TDA1308
? PCF8583
? MC33260
? STV9379
? MSP34XXG
? LM358N
16.1. TDA8885:
16.1.1. GENERAL DESCRIPTION
The TDA 8885 is I 2 C-bus controlled singlechip TV processors, which are intended to be applied in
PAL/NTSC and multi-standard television receivers. These ICs are largely compatible with the TDA
884X/5X series. Also in this IC family we have versions with a mono intercarrier FM sound channel and
versions with a QSS IF amplifier.
The main difference between the TDA 884X/5X series and the TDA 886X/7X/8X series is that the latter
contains integrated sound band-pass (in mono FM versions) and trap circuits, a switchable group delay
correction circuit and a multi-standard colour decoder which needs only one inexpensive (12 MHz) reference
crystal for all standards.
Furthermore various picture improvement features have been included.
16.1.2. FEATURES
• Multi-standard vision IF circuit with an alignment-free PLL demodulator without external components
• Internal (switchable) time-constant for the IF-AGC circuit
• Switchable sound trap and group delay correction circuit for the demodulated CVBS signal
• Flexible source selection with CVBS switch and a Y (CVBS)/C input so that a comb filter can be
applied
• Integrated chrominance trap circuit
• Integrated luminance delay line with adjustable delay time
• Integrated chroma band-pass filter with switchable centre frequency
• Colour decoder which needs only one 12 MHz reference crystal (or external clock signal) for all
standards
• Blanking of the ‘helper signals’ for PAL PLUS and EDTV-2
• Several picture improvement features.
• Internal base-band delay line
• YUV interface
• Linear RGB input and fast blanking
• RGB control circuit with ‘Continuous Cathode Calibration’, white point and black level offset
adjustment so that the colour temperature of the dark and the light parts of the screen can be chosen
independently.
• Adjustable peak white limiting circuit
• Half-tone (contrast reduction) possibility during mixed-mode of OSD and text signals
• Possibility to insert a ‘blue back’ option when no video signal is available
• Horizontal synchronisation with two control loops and alignment-free horizontal oscillator
• Vertical count-down circuit
• Vertical driver optimised for DC-coupled vertical output stages for improved geometry
• Vertical geometry processing.
• Low-power start-up for the horizontal drive circuit
• I 2 C-bus control of various functions
• QSS sound IF amplifier
• AM sound demodulator
• PAL decoder
• SECAM decoder
• NTSC decoder
• Additional RGB/ YUV input
• Black stretch and Blue stretch
• Dynamic skin tone control and coring on complete video signal
• Video dependent coring and Colour Transient Improvement
• White stretch and green enhancement
• Horizontal geometry (EW)
• Horizontal and vertical zoom
• Horizontal parallelogram and angle correction
• 2 nd CVBS output
• Additional YUV/ RGB input with saturation control
• 2 (I 2 C- bus controlled) switch outputs, which can be used to switch external circuits
16.1.3. Pin Description
1 IF input 1
2 IF input 2
3 EHT/overvoltage protection input
4 vertical sawtooth capacitor
5 reference current input
6 ground (vision/QSS IF amplifier and sound)
7 tuner AGC output
8 de-emphasise (front-end sound out) or selected sound out or AM sound in (1) SIF input 1
9 decoupling sound demodulator SIF input 2
10 narrow-band PLL filter AGC sound IF
11 external audio input QSS intercarrier out or AM output or external audio input (2)
12 internally connected
13 half tone (contrast reduction)
14 low-power start-up
15 IF-PLL loop filter
16 IF video output
17 serial clock input
18 serial data input/output
19 white stretch capacitor
20 chrominance input (S-VHS)
21 external CVBS/Y 3 input
22 output switch 1 (I 2 C)
23 main supply voltage (+8V) (vision/QSS amplifier, filters, CTI and sound)
24 internal CVBS input
25 ground 1 (colour decoder and synchronisation)
26 CVBS-2 output
27 audio out (volume controlled) / IF video out (3) AM audio output (volume controlled)
28 SECAM PLL decoupling
29 CVBS/Y 2 input
30 black-current input
31 blue output
32 green output
33 red output
34 beam current limiter input/V-guard input
35 red input for insertion
36 green input for insertion
37 blue input for insertion
38 RGB insertion input
39 luminance input
40 luminance output
41 2nd V/R input
42 2nd Y/G input
43 2nd U/B input
44 2nd RGB insertion input
45 U signal output or YUV-RGB insertion input (4)
46 V signal output or Y input or G input (4)
47 U or B signal input (4)
48 V or R signal input (4)
49 Ref. signal out or AVL or V-sync out (5) Ref. signal out or AM out or V-sync out (5)
50 decoupling digital supply
51 12 MHz crystal connection
52 12 MHz crystal connection
53 2nd supply voltage (+8 V) (colour decoder, control, synchronisation and geometry)
54 CVBS-1 output
55 bandgap decoupling
56 horizontal output
57 flyback input / sandcastle output
58 phase-2 filter
59 phase-1 filter
60 output switch 2 (I 2 C)
61 ground 2 (filters, CTI, control and geometry)
62 east-west drive output / Automatic Volume Levelling
63 vertical drive B output
64 vertical drive A output
SYMBOL PARAMETER MIN. TYP. MAX. UNIT
Supply
VP supply voltage 8.0 V
IP supply current tbf mA
Input voltages
Vi(VIF)(rms) video IF amplifier sensitivity (RMS value) 35 V
Vi(SIF)(rms) sound IF amplifier sensitivity (RMS value) 60 V
Vi(CVBS/Y)(p-p) external CVBS/Y input (peak-to-peak value) 1.0 V
Vi(CHROMA)(p-p) external chroma input voltage
(burst amplitude)(peak-to-peak value) 0.3 V
Vi(RGB)(p-p) RGB inputs (peak-to-peak value) 0.7 V
Vi(YI)(p-p) luminance input signal (peak-to-peak value) 1.4/1.0 V
Vi(UI)(p-p) U input signal (peak-to-peak value) 1.33/+0.7 V
Vi(VI)(p-p) V input signal (peak-to-peak value) 1.05/+0.7 V
Output signals
Vo(IFVO)(p-p) demodulated CVBS output (peak-to-peak value) 2.5 V
Io(AGCOUT) tuner AGC output current range 0 5 mA
Vo(QSSO)(rms) sound IF intercarrier output (RMS value) 100 mV
Vo(AMOUT)(rms) demodulated AM sound output (RMS value) 500 mV
Vo(CVBSO)(p-p) CVBS output voltage video switch (peak-to-peak value) 2.0 V
Vo(VO/I)(p-p) ?V output/input voltage (peak-to-peak value) 1.05 V
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