Phase Lock Loop ( PLL ) Using 565 9035

Categories: Linear Circuits


ADTRON’s Phase Lock Loop ( PLL ) using 565 is a versatile self – contained stand alone unit, useful in the study and demonstration of the principle and working of PLL and to find the lock and capture range of a PLL for different Voltage Controlled Oscillator ( VCO ) frequencies. The circuit consists of IC 565 with two different values of timing capacitor and a pot for fine variation in the VCO frequency. Input is to be applied from a Function Generator and output to be observed on CRO. The Trainer is enclosed in a special designed elegant powder coated metal cabinet with intelligently designed layout on imported acrylic front panel, are some of its other features.


PLL Used                                                                :      IC 565.

Voltage Controlled Oscillator (VCO) :      Frequency is adjustable using external R&C.

Coarse Variation                                              :      Using 2 Capacitor Selectable using external links.

Fine Variation                                                    :      Using potentiometers provided on the front panel.

Test Point                                                              :      Multi – coloured test points at various stages in the circuit to observe waveforms and voltage.

Indicator                                                                :      Mains.

Power Requirement                                       :      230V, 50Hz AC 1f.

Standard Accessories                                    :      Detailed instruction manual.


1.      To determine the free running frequency F0 of VCO for different coarse and fine settings and verify it theoretically.

2.      To determine the lock range and capture range for different VCO frequency and verify it theoretically.