Daewoo DTY-21U7/21B4, DTZ-29U7/U3, DTZ-2881/28W8, DTC-21Y1/21Y2, DTC-20T2 Synchronisation circuit

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CP-520/520A/520F Service Manual

The Ics have 3 inputs for external CVBS signals. All CVBS inputs can be used as Y input for the insertion of Y/C signals.However, the CVBS(Y)2 input has to be combined with the C3 input. It is possible to add and extra CVBS(Y/C) input via the pins which are intended to be used for YUV interface (or RGB/YPrPb input). The selection of this additional CVBS(Y/C) input is made via the YC bit.

The function of the IFVO/SVO/CVBSI pin is determined by the SVO1/SVO0 bits. When used as output a selection can be made between the IF video output signal or the selected CVBS signal (monitor out). This pin can also be used as additional CVBS input. This signal is inserted in front of the group delay / sound trap circuit. It is also possible to use the group delay and sound trap circuit for the CVBS2 signal (via the CV2 bit).

For the CVBS(Y/C) inputs the circuit can detect whether a CVBS or Y/C signal is present on the input. The result can be read from the status register (YCD bit in subaddress 03H) and this information can be used to put the input switch in the right position (by means of the INA-IND bits in subaddress 38H). The Y/C detector is only active for the CVBS(Y)3/C3, CVBS(Y)4/C4 and CVBS(Y)x/Cx inputs. It is not active for the CVBS(Y)2/C3 input.

The video ident circuit can be connected to all video input signals. This ident circuit is independent of the synchronisation and can be used to switch the synchronisation and can be used to switch the presence of a video signal (via the VID bit). In this way a very stable OSD can be realised. The result of the video ident circuit can be read from the output bit SID (subaddress 00).

5.2.6 Synchronisation circuit

The IC contains separator circuits for the horizontal and vertical sync pulses. To obtain an accurate timing of the displayed picture the input signal of the sync separator is not derived from the various CVBS/Y or RGB/YPrPb inputs but from the YOUT pin. For this reason the YOUT pin must be capacitively coupled to the YSYNC pin. The delay between the various inputs and the YOUT signal can have rather large differences (e.g. comb filter active or not). By choosing the YOUT signal as input signal for the sync separator these delays have no effect on the picture position. Only for RGB signals without sync on green the input of the sync separator has to be connected to one of the CVBS inputs. This selection is made by means of the SYS bit.

The horizontal drive signal is obtained from an internal VCO which is running at a frequency of 25 MHz. This oscillator is stabilised to this frequency by using the clock signal coming from the reference oscillator of the TCG -Controller.

To obtain a stable On-Screen-Display (OSD) under all conditions it is important that the first control loop is switched off or set to low gain when no signal is available at the input. The input signal condition is detected by the video identification circuit. The video identification circuit can automatically switch first control loop to a low gain when no input signal is available. This mode is obtained when the VID bit is set to “0”. When the VID bit is “1” the mode of the first control loop can be switched by means of the FOA/FOB or POC bits.

For a good performance during normal TV reception (display of the front-end signal) various connections are active between the vision IF amplifier and the synchronisation circuit (e.g. gating pulses for the AGC detector and noise gating of the sync separator). These connections are not allowed when external video signals are displayed. The switching of these connections can be coupled to the input signal selection bits (INA-IND). This mode is obtained when the VDXEN bit is “0”. Due to the input signal selector configuration it is possible that the internal CVBS signal is

DTV R&D Europe

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Contents Color Television Chassis CP-520 TDA8946J Stereo Audio Amplifier Contents Document History Main Features SpecificationsIC Description UOC III Series TDA8358J Vertical AmplifierALL Versions Schematic DiagramStereo and AV Stereo Versions Mono Versions Functional Description Sound ProcessorDocument History Version Date Comments EURO-SCART 1 21 Pin Signal Description Matching value GeneralPin Signal Description Matching value EURO-SCART 2 21 PinCHANNEL/FREQUENCY Table Channel Europe Ccir France Gbireland East OirtC48 C46C47 C49S20 S18S19 S21Product Safety Notice Safety Instruction RAY Radiation PrecautionSafety Precaution Order Default setting Microcontroller Configuration Service ModeService Mode Navigation HOR CEN RED Gain GRN Gain Blue Gain RED Bias GRN BiasRemarks Tuner OptionsChassis Model Option Navigation in NVM Editor mode Entering into Factory modeEntering into NVM Editor mode Exit NVM Editor modeNVM Data Change List Vertical Geometry 1 G2 AlignmentWhite Balance Horizontal Picture CentringCorner B & Corner T EW Trapez 7 AGCBulgarian IC DescriptionIC Marking and Version CZECH, German DANISH, SpanishBlock Diagram QFP 128pin Short DescriptionGND3 BlkinBclin PBIN3GND2 SIFAGC/DVBAGCPllif QSSO/AMOUT/AUDEEAnalogue video processing stereo versions FeaturesAnalogue Video Processing all versions Analogue video processing mono versionsStereo Demodulator and Decoder full stereo versions Audio interfaces and switching mono versionsSound Demodulation all versions Controller Audio Multi Channel Decoder stereo versions with Audio DSPRDS/RBDS TDA8946J Stereo Audio Amplifier Data CaptureDisplay OUT1+ Pin Symbol DescriptionOUT1 ModeBlock diagram TDA8946J TDA8358J Vertical Amplifier 1 TDA8358JOutb INAINB InewGND FeaturesPin description Pin No Name Description General Description IIN H PIN Description Name SymbolOVP TJ TSDOCH F Mosfet Electrical Characteristics IC PIN Rating DescriptionSymbol MIN Type MAX Unit Circuit Description QSS sound circuit Functional Description of Video ProcessorVision if amplifier FM demodulatorMono Versions Audio input selector and volume controStereo and AV Stereo Versions ALL VersionsSynchronisation circuit Horizontal and vertical drive Colour decoder RGB output circuit Wprgb Write registers 11 I2C-BUS User Interface DescriptionPossible slave address Read registersOther features of the Demdec are Analog 2-CARRIER Systems Table Frequency modulationA2+ Korea ParameterA2/A2 CarriersystemswithnicamFunctional Overview Of the digital controller sound part Fmandamdemodulation IntroductionMixer Fmpilotcarrierpresentdetector FmidentificationFM/AMDECODING NicamdemodulationNicam AUTO-MUTE Service Parts List DTV- R&D Europe CCXB1H561K Cera Carbon Film Carbon Comp DTC-20T2FZS-S E30 4856310300 PCB Main CP-520A DTC 100 OHM J J500 85801065GY Packing AS DTC-20T2FZS-S DTC-21Y1FZF-S E33 4856310300 1N4937G 2.2K OHM F Packing AS DTC-21Y1FZF-S DTZ-29U7FZF-S Partsname 3M #232 6.0X2000M A001 4859809993 J38 85801065GY Packing AS DTZ-29U7FZS-S Exploded View Exploded View 7-2DTY-2880 Exploded View 7-3DTY-21U7 Exploded View 7-4DTY-25G6 Exploded View 7-5DTC-20T2 Exploded View 7-6DTC-21Y1 Exploded View 7-7DTZ-29U7 Exploded View 7-8DTZ-2881 Exploded View 7-9DTZ-2481 Printed Circuit Board 4859809893CP-520A 4859809993CP-520F Schematic Diagram CP-520A CP-520F

DTZ-2481, DTZ-29U7/U3, DTC-21Y1/21Y2, DTY-21U7/21B4, DTY-2880/28W5 specifications

The Daewoo DTC-20T2, DTY-28A8, DTY-28A6, DTY-28A7, DTZ-2881/28W8, DTY-25G6/25G7, and DTY-2880/28W5 represent a range of innovative and feature-rich vehicles that reflect Daewoo's commitment to quality and advanced technology. Each model combines sleek design with performance excellence, appealing to a wide range of consumers.

Starting with the DTC-20T2, this compact car offers a combination of efficiency and agility. Its lightweight design enhances fuel economy while maintaining stability on the road. Equipped with a state-of-the-art engine, the DTC-20T2 delivers a responsive drive, making it ideal for city commuting and weekend getaways.

The DTY-28A8 is known for its spacious interior and comfort features. It boasts advanced infotainment systems, including touch screens and smartphone connectivity, catering to modern drivers. Safety is paramount, with multiple airbags and advanced braking systems ensuring peace of mind on every journey.

Similarly, the DTY-28A6 and DTY-28A7 share many design elements but have unique enhancements that differentiate them. They incorporate advanced suspension systems that provide a smooth driving experience while navigating urban and rural landscapes. These models also feature high-efficiency engines that strike a balance between power and fuel consumption.

Moving to the DTZ-2881/28W8, this vehicle makes a statement with its bold design and robust performance. This model is designed with aerodynamics in mind, reducing drag and enhancing fuel efficiency. It includes innovative technologies like regenerative braking, which captures energy during deceleration, extending the vehicle's overall efficiency.

The DTY-25G6/25G7 and DTY-2880/28W5 are particularly impressive with their emphasis on versatility. These models offer various configurations and layouts to cater to different needs, whether for families or individuals. They feature expanded cargo capacity and modular seating arrangements that can accommodate both passenger and transportation requirements.

In conclusion, the Daewoo DTC-20T2, DTY-28A8, DTY-28A6, DTY-28A7, DTZ-2881/28W8, DTY-25G6/25G7, and DTY-2880/28W5 showcase a blend of performance, technology, and comfort across their varying models. From advanced safety features to innovative fuel efficiency technologies, these vehicles are tailored to meet the needs of a diverse clientele, reinforcing Daewoo’s stature in the automotive industry.
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