different phase voltages

[DHANANJAYA L]

Dear Sir i am doing a project on pic16f877a for multichannel ADC i.e 3 phase 415 volts Analog voltage to digital voltage using PIC ADC on display on LCD 4 bit mode using 4 MHZ XT crystal oscillator . I have sucessfully find the digital voltage in single phase but I am to do the three phase voltage in a single PIC chip . I think PIC doesn't support different phase voltage i.e reference voltages(Vref+ & Vref_). I have using separate step down transformers to 5 volts. I have tried the AC to DC conversion and connect to PIC analog pins. the digital voltages ADC is fluctions it doen't give constant voltages irregularly..Please if you any solutions please let me know with circuits & code

Thanks & Reagards
Dhananajaya

 

[abhi_tandon80]

Put a Electrolytic capacitor between MICRO ADC pin and GND it will add remember it will add some delay in software !

 

[BradtheRad]

If the aim is to create 120 and 240 degree phase delays, then capacitors to ground can be added in sufficient stages:



Values are not critical since the potentiometers allow you to tune the desired time delay.

Each successive waveform is attenuated.