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uPD2812 PLL Integrated Circuits


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 8 bit BCD binary programmable divide-by-N counter or 6 bit ROM programmable divide-by-N counter. The ROM-table is programmed from factory to 40 channels.

2FINVCO Oscillator Input
3MSMode Select - HIGH=40 Channels ROM - LOW=Binary input (N=3-255)
4POProgramable Divider Output
5DOReference Divider Output
6AOLoop filter Amplifier Output
7AILoop filter Amplifier Input
8PDPhase Detector output
9LDLoop Detector output - Locked=HIGH Unlocked=LOW
10VDDPositive Power Supply (+5Volt)
12P1Binary programable input 1
13P2Binary programable input 2
14P3Binary programable input 3
15P4Binary programable input 4
16P5Binary programable input 5
17P6Binary programable input 6
18P7Binary programable input 7
19P8Binary programable input 8
201/2RReferency frequency divided by 2
21RIReferency oscillator Input (X-tal)
22RORefeerency oscillator Output (X-tal)

Explanation of pin function terms

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