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INTEGRATED CIRCUITS
DDEAVITCAE SSPEHCIEFIECATTION
TDA955X/6X/8X PS/N1 series TV signal processor-Teletext decoder with embedded µ-Controller
Tentative Device Specification FVielersuionnd:e1r.I6ntegrated Circuits,
2000 Jun 22 Previous date: 2000 Apr 06
Philips Semiconductors
TV signal processor-Teletext decoder with embedded µ-Controller
Tentative Device Specification
TDA955X/6X/8X PS/N1 series
GENERAL DESCRIPTION
The various versions of the TDA955X/6X/8X PS/N1 series combine the functions of a video processor together with a µ-Controller and US Closed Caption decoder. Several versions have a Teletext decoder on board. The Teletext decoder has an internal RAM memory for 1or 10 page text. The ICs are intended to be used in economy television receivers with 90° and 110° picture tubes.
The ICs have supply voltages of 8 V and 3.3 V and they are mounted in an S-DIP 64 envelope.
The features are given in the following feature list. The differences between the various ICs are given in the table on page 4.
FEATURES
TV-signal processor
• Multi-standard vision IF circuit with alignment-free PLL demodulator
• Internal (switchable) time-constant for the IF-AGC circuit
• A choice can be made between versions with mono intercarrier sound FM demodulator and versions with QSS IF amplifier. In the QSS versions without East-West output an AM/FM mode can be activated. In that case both the QSS amplifier (for AM demodulation) and the FM demodulator are available.
• The mono intercarrier sound circuit has a selective FM-PLL demodulator which can be switched to the different FM sound frequencies (4.5/5.5/6.0/6.5 MHz). The quality of this system is such that the external band-pass filters can be omitted.
• The FM-PLL demodulator can be set to centre frequencies of 4.74/5.74 MHz so that a second sound channel can be demodulated. In such an application it is necessary that an external bandpass filter is inserted.
• The QSS amplifier and mono intercarrier sound circuit of some versions can be used for the demodulation of FM radio signals
• Source selection between the ‘internal’ CVBS and one external CVBS or Y/C signal
• Integrated chrominance trap circuit
• Integrated luminance delay line with adjustable delay time
• Picture improvement features with peaking (with switchable centre frequency, depeaking, variable positive/negative overshoot ratio and video dependent coring) and blue- and black stretching
• Integrated chroma band-pass filter with switchable centre frequency
• Only one reference (12 MHz) crystal required for the µ-Controller, Teletext- and the colour decoder
• PAL/NTSC or multi-standard colour decoder with automatic search system
• Internal base-band delay line
• Indication of the Signal-to-Noise ratio of the incoming CVBS signal
• RGB control circuit with ‘Continuous Cathode Calibration’, white point and black level off-set adjustment so that the colour temperature of the dark and the light parts of the screen can be chosen independently.
• A linear RGB/YUV/YPBPR input with fast blanking for external RGB/YUV sources. The synchronisation circuit can be connected to the incoming Y signal. The Text/OSD signals are internally supplied from the µ-Controller/Teletext decoder.
• Contrast reduction possibility during mixed-mode of OSD and Text signals
• Adjustable ‘wide blanking’ of the RGB outputs
• Horizontal synchronization with two control loops and alignment-free horizontal oscillator
• Vertical count-down circuit
• Vertical driver optimized for DC-coupled vertical output stages
• Horizontal and vertical geometry processing
• Horizontal and vertical zoom function for 16 : 9 applications
• Horizontal parallelogram and bow correction for large screen picture tubes
• Low-power start-up of the horizontal drive circuit
2000 Jun 22
2
Philips Semiconductors
TV signal processor-Teletext decoder with embedded µ-Controller
Tentative Device Specification
TDA955X/6X/8X PS/N1 series
µ-Controller
• 80C51 µ-controller core standard instruction set and timing
• 1 µs machine cycle • 32 - 128Kx8-bit late programmed ROM • 3 - 12Kx8-bit Auxiliary RAM (shared with Display and
Acquisition)
• Interrupt controller for individual enable/disable with two level priority
• Two 16-bit Timer/Counter registers • One 16 bit Timer with 8-bit Pre-scaler • WatchDog timer • Auxiliary RAM page pointer • 16-bit Data pointer • Stand-by, Idle and Power Down (PD) mode • 14 bits PWM for Voltage Synthesis Tuning • 8-bit A/D converter • 4 pins which can be programmed as general I/O pin,
ADC input or PWM (6-bit) output
Data Capture
• Text memory for 0, 1 or 10 pages • In the 10 page versions inventory of transmitted Teletext
pages stored in the Transmitted Page Table (TPT) and Subtitle Page Table (SPT)
• Data Capture for US Closed Caption • Data Capture for 525/625 line WST, VPS (PDC system
A) and Wide Screen Signalling (WSS) bit decoding
• Automatic selection between 525 WST/625 WST • Automatic selection between 625 WST/VPS on line 16
of VBI
•.