Datasheet TDA8360; TDA8361; TDA8362 (Philips) - 9

Philips Semiconductors Objective specification Integrated PAL and PAL/NTSC TV TDA8360; TDA8361; TDA8362 processors
Sound circuit
The oscillator network is internal. When the pin is left open-circuit the Because of the spread of internal trap is switched off so that the circuit The sound bandpass and trap filters components an automatic adjustment can also be used for S-VHS have to be connected externally. The circuit has been added to the IC. applications. filtered intercarrier signal is fed to a The circuit compares the oscillator limiter circuit and is demodulated by The luminance delay line and the frequency with that of the crystal means of a PLL demodulator. The delay for the peaking circuit are also oscillator in the colour decoder. This PLL circuit tunes itself automatically realised by means of gyrator circuits. results in a free-running frequency to the incoming signal, consequently, which deviates less than 2% from the no adjustment is required.
Colour decoder
typical value. The volume is DC controlled. The The colour decoder in the various ICs The circuit employs a second control composite audio output signal has an contains an alignment-free crystal loop to generate the drive pulses for amplitude of 700 mV RMS at a oscillator, a colour killer circuit and the horizontal driver stage. volume control setting of −6 dB. The colour difference demodulators. de-emphasis capacitor has to be X-ray protection can be realised by The 90° phase shift for the reference connected externally. The switching the pin of the second signal is achieved internally. Because non-controlled audio signal can be control loop to the positive supply line. the main differences of the 3 ICs are obtained from this pin via a buffer The detection circuit must be found in the colour decoder the stage. The amplitude of this signal is connected externally. When the X-ray various types will be discussed. 350 mV RMS. protection is active the horizontal output voltage is switched to a high
TDA8360
The TDA8361 and TDA8362 external level. When the voltage on this pin audio input signal must have an This IC contains only a PAL decoder. returns to its normal level the amplitude of 350 mV RMS. The Depending on the frequency of the horizontal output is released again. audio/video switch is controlled via crystals which are connected to the IC the chrominance input pin. The IC contains a start-up circuit for the decoder can demodulate all PAL the horizontal oscillator. When this standards. Because the horizontal
Synchronization circuit
feature is required a current of 6.5 mA oscillator is calibrated by using the has to be supplied to pin 36. For an crystal frequency as a reference the The sync separator is preceded by a application without start-up both 4.4 MHz crystal must be connected to voltage controlled amplifier which supply pins (10 and 36) must be pin 35 and the 3.5 MHz crystal to adjusts the sync pulse amplitude to a connected to the 8 V supply line. pin 34. When only one crystal is fixed level. The sync pulses are then connected to the IC the other crystal fed to the slicing stage (separator) The drive signal for the vertical ramp pin must be connected to the positive which operates at 50% of the generator is generated by means of a supply rail via a 47 kΩ resistor. For amplitude. divider circuit. The RC network for the applications with two 3.5 MHz ramp generator is external. The separated sync pulses are fed to crystals both must be connected to the first phase detector and to the pin 34 and the switching between the
Integrated video filters
coincidence detector. The crystals must be made externally. coincidence detector is used for The circuit contains a chrominance Switching of the crystals is only transmitter identification and to detect bandpass and trap circuit. The filters allowed directly after the vertical whether the line oscillator is are realised by means of gyrator retrace. The circuit will indicate synchronized. When the circuit is not circuits and are automatically tuned whether a PAL signal has been synchronized the voltage on the by comparing the tuning frequency identified by the colour decoder via peaking control pin (pin 14) is LOW with the crystal frequency of the the saturation control pin. so that this condition can be detected decoder. When two crystals are connected to externally. The first PLL has a very In the TDA8361 and TDA8362 the the IC the output voltage of the video high static steepness, this ensures chrominance trap is active only when identification circuit indicates the that the phase of the picture is the separate chrominance input pin is frequency of the incoming independent of the line frequency. connected to ground or to the positive chrominance signal. The line oscillator operates at twice supply voltage and when a colour the line frequency. signal is recognized. March 1994 9