The device is a single-chip PLL frequency synthesizer designed for TV and VCR tuning systems.
The circuit consists of a divide-by-eight prescaler with its own preamplifier, a 15-bit programmable divider, a crystal oscillator and its programmable reference divider and a phase/frequency detector combined with a charge-pump which drives the tuning amplifier and the 33 V output.
Four high-current PNP band switch buffers are provided for band switching. Two PNP buffers can be switched on simultaneously. The sum of the collector currents is limited to 50 mA.
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