Author Topic: Square Wave to Sine Wave Conversion Problem (Read 517 times)

wastedEffort · « **on:** July 02, 2010, 08:30:17 PM »

I used a Butterworth Pi Model for my Lowpass Filter to be able to convert a square wave to a sine wave but the output sine wave i'm getting was very small compared to the original square wave. Also, the square wave gets attenuated if i connect the lowpass filter to the circuit which gives the square wave as its output. What could be causing this problem?

Philippine Electronics Forum · « **on:** July 02, 2010, 08:30:17 PM »

labgruppen · « **Reply #1 on:** July 02, 2010, 08:45:15 PM »

For the very low output signal compared to the input, it may be due to too low cut-off frequency compared to your actual frequency. And for the input square wave signal to get attenuated everytime you connect your LPF, it may be due to your LPF loading down your square wave source which may be related to the previous scenario, too low cut-off frequency, especially if you used only RC elements in your filter.

Philippine Electronics Forum · « **Reply #1 on:** July 02, 2010, 08:45:15 PM »

wastedEffort · « **Reply #2 on:** July 02, 2010, 10:08:09 PM »

I used inductor and capacitors. My square wave frequency is 8.33kHz. What cut-off frequency should i use to obtain a sine wave very close in amplitude to my square wave?

Philippine Electronics Forum · « **Reply #2 on:** July 02, 2010, 10:08:09 PM »

wastedEffort · « **Reply #3 on:** July 04, 2010, 05:44:08 PM »

i want to vary the frequency of my square wave so i want my lowpass filter to accommodate the change in frequency..

Philippine Electronics Forum · « **Reply #3 on:** July 04, 2010, 05:44:08 PM »

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