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LC7130, LC7131, LC7135, LC7136 and LC7137 PLL Frequency Synthesizer

Overview

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.
PinNameDescription
1P1Programmable input 1
2P2Programmable input 2
3P3Programmable input 3
4P4Programmable input 4
5P5Programmable input 5
6P6Programmable input 6
7TestConnect to GND
8CH19Called channel 19 when pins are HIGH
9CH9Called channel 9 when pins are HIGH
10MC
11RIX-tal Input
12ROX-tal Output
13GNDGround
14LDLocked=HIGH Unlocked=LOW
15PDPhase Detector Output
16AILoop filter Amplifier Input
17AOLoop filter Amplifier Output
18VccPositive Supply Voltage
19F inVCO Frequency Input
20T/RTransmit=LOW Receive=HIGH

Explanation of pin function terms


Programming Chart for LC7130/LC7131/LC7132

ChannelRX
Divided by
TX
Divided by
132543345
232563347
..........
2233063397
..........
4033423433
NOTES:
1. 91-count upshift on TX provides 455kHz offset for receiver IF mixing.
2. Reference and Programmable Dividers use 5kHz steps.

Example of VCO Determination, Channel 1:
3254 x 5kHz = 16.270MHz (RX-Mode)
3345 x 5kHz = 16.725MHz (TX-Mode)

Programming Chart for LC7136/LC7137

ChannelRX
Divided by
TX
Divided by
133812760
233832761
..........
4034592799
NOTES:
1. Referency and Programmable Dividers use 5kHz steps.
2. TX VCO frequency is doubled to provide direct on-channel frequency.

Example of VCO Determination, Channel 1:
3381 x 5kHz = 16.905MHz (RX-Mode)
2760 x 5kHz = 13.800MHz (TX-Mode)
(13.800MHz x 2 = 27.600MHz + 1.25kHz tuned offset = 27.60125MHz)


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