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LC7120 PLL Frequency Synthesizer


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 6 bit ROM programmable divide-by-N counter. The ROM-table is programmed from factory.

1P1Programmable input 1
2P2Programmable input 2
3P3Programmable input 3
4P4Programmable input 4
5P5Programmable input 5
6P6Programmable input 6
7IFSIF Select - HIGH=10.695MHz LOW=9.785MHz
8T/RTransmit=LOW Receive=HIGH
9VccPositive Supply Voltage
10RIX-tal Input
11ROX-tal Output
12RBOscillator Output (Buffered)
131/2RReferency oscillator output divided by 2
14F inVCO Frequency Input
15LD2Loock Detector 2
16LD1Loock Detector 1
17PDPhase Detector Output
18AILoop filter Amplifier Input
19AOLoop filter Amplifier Output

Explanation of pin function terms

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