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1 Video ICs Single chip Hi-Fi audio signal processor BH7802K The BH7802K incorporates the functions for a VHS audio signal processing system on a single chip. The circuits on the chip are a peak-noise reduction processor (PNR), an FM modulator / demodulator circuit, an I / O switcher, an automatic FM detector circuit, an FM bandpass filter, and a regulator circuit. • Applications VCR S • Features 1) Operates off dual ± power supply which allows a large reduction in the number of coupling capacitors required. A built-in regulator makes it easy to con- struct a power supply system. 2) A two-line I 2 C bus control decoder circuit is provid- ed, allowing the various IC modes to be set using serial control. 3) A four line input switcher is included (tuner, BS, and line 1 / 2). The output switcher can switch between STEREO, LEFT, and RIGHT, and Hi-Fi, MIX, and NORMAL, and a BS MONITOR function is also pro- vided. The MIX AMP is AV-LINK compatible. 4) The PNR processor and FM modulator / demodula- tor circuit have reversed characteristics at recording and playback. In addition, the adjustment for carrrier frequency and FM deviation / playback level are common. 5) The built-in bandpass filter excels at attenuation of other channels, and can be directly coupled to the playback amplifier. The FM recording output block has a high-performance low-pass filter to produce sine wave output. 6) Slope-control-type FM-switching-noise compensa- tion circuit. 7) Envelope detector circuit and noise-detector-type automatic FM detector circuit. 8) VCO that uses the color signal sub-carrier frequency fsc (NTSC: 3.579545MHz, PAL: 4.433619MHz) and auto-adjusting BPF circuit ensure stable adjustment with no fluctuation due to mounting stress or time. • Absolute maximum ratings (Ta = 25°C) Parameter Applied voltage Storage temperature V CC VEE VIN Tstg 18, 36pin······························ 6.0 39pin································· – 6.0 5, 6, 32pin···························· 6.5 Pins other than the above···· 6.0 – 55 ~ + 125 V SymbolLimitsUnit V V VINV Power dissipationPd 850 ∗ mW Operating temperatureTopr – 10 ~ + 70°C °C ∗ Reduced by 8.5mW for each increase in Ta of 1°C over 25°C, when mounted on a 70mm × 70mm, t = 1.6mm glass epoxy board.