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This 27 MHz band, PLL frequency synthesizer LSI chip is designed specifically for CB transceivers. The integrated circuit`s incorporates PLL circuitry and a controller for CB applications on a single CMOS chip.
This PLL-circuit use a 9 bit BCD binary programmable divide-by-N counter. This PLL-circuit use a 9 bit BCD/ROM programmable divide-by-N counter. The ROM-table is programmed from factory to 40 channels CEPT.

Down-converting of the frequency to the divider

This PLL Circuit use a Mixer and a X-Tal Oscillator to convert the output frequency f OUT to the f IN to the PLL Circuit.
The X-Tal frequency is f XTAL = f OUT - f IN
The output frequency can be changed by changing the mixing-xtal or add a new mixing-xtal to the oscillator.

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