Building a Phase Lock Loop from individual circuits.

[electronice]

I am trying to build a working PLL based on the 4046.

The circuit I'm using has a small bandwidth and operates at a low frequency with a constant 50% duty cycle (square wave) so I will use the Exclusive-OR Low Noise Phase Detector from the 4046.

I have the TI app notes on the 4046 but the phase detector seems a bit extravagent.

Does anyone know where I can find a simplier schematic for a Exclusive-OR low noise phase detector?

[johnsold · Accepted solution]

The TI data sheet for the 4046 is derived directly from the RCA data sheets (via Harris Semiconductor).  I have designed several PLL circuits using that datasheet.  The XOR phase detector in the 4046 is as far as I know just an XOR gate.  The Signal Input pin has some special bias circuitry to allow its use with signals much smaller than logic levels.

If you have logic-level signals, you can use any XOR gate.

Lynn

[Jiek]

Could you tell me how to add 4046 PLLchip,plese? Thanks!