Other useful info

Last modified 2007-05-02


PLL frequency synthesizer


This PLL-circuit use an 8 bit BCD binary programmable divide-by-N counter.

Down-converting of the frequency to the divider

This PLL circuit use a mixer and a XTAL 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.
1VDDPositive oower supply
2F inVCO oscillator input
3RIReference oscillator input (10.240MHz)
4FSHigh=10kHz - Low=5kHz
5PDVCO voltage out
6LDLoop detected - High=Locked Low=Unlocked
7P outProg. Out
8P7Programmable input (Binary)
9P6Programmable input (Binary)
10P5Programmable input (Binary)
11P6Programmable input (Binary)
12P3Programmable input (Binary)
13P2Programmable input (Binary)
14P1Programmable input (Binary)
15P0Programmable input (Binary)

See also the explanation of PLL pin functions