Datasheet TDA8360; TDA8361; TDA8362 (Philips) - 8

Philips Semiconductors Objective specification Integrated PAL and PAL/NTSC TV TDA8360; TDA8361; TDA8362 processors To overcome this problem a speed-up
SYMBOL PIN DESCRIPTION
circuit has been included which VFB 41 vertical feedback input detects whether the AGC detector is VRAMP 42 vertical ramp generator activated every frame period. If, VOUT 43 vertical output during a 3-frame period, no action is detected the speed of the system is AFCOUT 44 AFC output increased. When the incoming signal IFIN1 45 IF input 1 has no peak white information (e.g. IFIN2 46 IF input 2 test lines in the vertical retrace period) AGCOUT 47 tuner AGC output the gain would be video signal dependent. To avoid this effect the DECAGC 48 AGC decoupling capacitor circuit also contains a black level TUNEADJ 49 tuner take-over adjustment AGC detector which is activated when AUOUT 50 audio output the black level of the video signal exceeds a certain level. DECDEM 51 decoupling sound demodulator DEC The TDA8361 and TDA8362 contain BG 52 decoupling bandgap supply a video identification circuit which is independent of the synchronization
TDA8360
The reference carrier for the video circuit. Therefore search tuning is demodulator is obtained by means of The TDA8360 has the following possible when the display section of passive regeneration of the picture differences to the pinning: the receiver is used as a monitor. In carrier. The external reference tuned the TDA8360 this circuit is only used Pin 6: external audio input not circuit is the only remaining for stable OSD at no signal input. In connected adjustment of the IC. the normal television mode the Pin 15: external CVBS input not In the TDA8362 the polarity of the identification output is connected to connected demodulator can be switched so that the coincidence detector, this applies the circuit is suitable for both positive to all three devices. The identification Pin 16: chrominance and A/V switch and negative modulated signals. output voltage is LOW when no input not connected transmitter is identified. In this The AFC circuit is driven with the Pin 27: hue control input not condition the sound demodulator is same reference signal as the video connected. switched off (mute function). When a demodulator. To ensure that the transmitter is identified the output video content does not disturb the
TDA8361
voltage is HIGH. The voltage level is AFC operation a sample-and-hold dependent on the frequency of the The TDA8361 has the following circuit is incorporated; the capacitor incoming chrominance signal. differences to the pinning: for this function is internal. The AFC output voltage is 6 V. Pin 1: only audio de-emphasis The AGC detector operates on levels, Pin 27: only hue control top sync for negative modulated and Pin 32: 4.43 MHz output for TDA8395 top white for positive modulated is not connected. signals.The AGC detector time constant capacitor is connected externally. This is mainly because of
FUNCTIONAL DESCRIPTION
the flexibility of the application.
Video IF amplifier
The time constant of the AGC system The IF amplifier contains during positive modulation 3 AC-coupled control stages with a (TDA8362) is slow, this is to avoid any total gain control range of greater visible picture variations. This, than 60 dB. The sensitivity of the however, causes the system to react circuit is comparable with that of very slowly to sudden changes in the modern IF ICs. input signal amplitude. March 1994 8