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MC145106 MM55106 MM55116 MM55126 PLL Frequency Synthesizer

Overview

The MC145106 is a phase­locked loop (PLL) frequency synthesizer constructed in CMOS on a single monolithic structure. This synthesizer finds applications in such areas as CB and FM transceivers. The device contains an oscillator/amplifier, a 1024 or 2048 divider chain for the oscillator signal, a programmable divider chain for the input signal, and a phase detector.
The MC145106 has circuitry for a 10.24 MHz oscillator or may operate with an external signal. The circuit provides a 5.12 MHz output signal, which can be used for frequency tripling. A 512 programmable divider divides the input signal frequency for channel selection. The inputs to the programmable divider are standard ground­to­supply binary signals. Pull­down resistors on these inputs normally set these inputs to ground enabling these programmable inputs to be controlled from a mechanical switch or electronic circuitry.
The phase detector may control a VCO and yields a high level signal when input frequency is low, and a low level signal when input frequency is high. An out­of­lock signal is provided from the on­chip lock detector with a ³0² level for the out­of­lock condition.
 Single Power Supply
 Wide Supply Range: 4.5 to 12 V
 Provision for 10.24 MHz Crystal Oscillator
 5.12 MHz Output
 Programmable Division Binary Input Selects up to N=512
 On­Chip Pull­Down Resistors on Programmable Divider Inputs
 Selectable Reference Divider, 1024 or 2048 (Including ÷ 2)
 Three­State Phase Detector

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.

Pin Name Description
1 VDD Positive Power Supply
2 F in Frequency input to programmable divider - Max. 3MHz
3 OSC in Oscillator input
4 OSC out Oscillator output
5 F out Reference OSC frequency divide by 2 output
6 FS Reference Oscillator Frequency Division Select. 1=10 kHz, 0=5 kHz
7 D out Detector output (for control of external VCO)
8 LD Lock Detector
9 P8 Programmable inputs (Binary)
10 P7 Programmable inputs (Binary)
11 P6 Programmable inputs (Binary)
12 P5 Programmable inputs (Binary)
13 P4 Programmable inputs (Binary)
14 P3 Programmable inputs (Binary)
15 P2 Programmable inputs (Binary)
16 P1 Programmable inputs (Binary)
17 P0 Programmable inputs (Binary)
18 VSS Ground

TRUTH TABLE
P8 P7 P6 P5 P4 P3 P2 P1 P0 Divide by N
0 0 0 0 0 0 0 0 0 2
0 0 0 0 0 0 0 0 1 3
0 0 0 0 0 0 0 1 0 2
0 0 0 0 0 0 0 1 1 3
0 0 0 0 0 0 1 0 0 4
0 0 0 0 0 0 1 0 1 5
0 0 0 0 0 0 1 1 0 6
0 0 0 0 0 0 1 1 1 7
0 0 0 0 0 1 0 0 0 8
- - - - - - - - - -
- - - - - - - - - -
0 1 1 1 1 1 1 1 1 255

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