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SM5124A PLL 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 8 bit ROM programmable divide-by-N counter. The ROM-table is programmed from factory to 40 channels.
1Q inInternal quartz crystal oscillator circuit input
2Q outInternal quartz crystal oscillator circuit output
3VDDPower supply 5,7 to 6,3 Volt
4LDUNLOCKED signal output. Unlocked: Low, Locked: High
5DOPhase detector output. Charge pump circuit for active filter
6AIAmplifier input
7AOAmplifier output
8T/RTransmit/receiving switch. Transmit: High, Receive: Low
9F inProgrammable counter input
10P0Channel switching input
11P1Channel switching input
12P2Channel switching input
13P3Channel switching input
14P4Channel switching input
15P5Channel switching input
16P6Channel switching input
17P7Channel switching input

Explanation of pin function terms

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