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Altera_Forum's avatar
Altera_Forum
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15 years ago

pulse generator (need help)

I want to generate 25Hz,50Hz,100Hz pulse signals!

The singal is bad when I use frequency division!

Is there a better way to generate the signals?

Thank you very much!

--a friend from China!

5 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    how are you dividing the signals? are you gating the clock?

    you'd be better off using a PLL or clock enble signals
  • Altera_Forum's avatar
    Altera_Forum
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    Why the signal is bad with frequency division?

    Do you use schematic or HDL code?
  • Altera_Forum's avatar
    Altera_Forum
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    --- Quote Start ---

    Why the signal is bad with frequency division?

    Do you use schematic or HDL code?

    --- Quote End ---

    i use verilog ,the square wave contains lots of high frequency waves!

    i also use PLL!
  • Altera_Forum's avatar
    Altera_Forum
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    Do you see the high frequency glitches experimentally?

    If yes, did your logic analyzer sample your output synchronously?

    If not sampling synchronously, it is normal that you see glitches.

    Remember that you only need that the outputs are stable and have the proper values one setup time before the next active clock edge.