Averager circuit for very low frequencies

Discussion in 'The Projects Forum' started by skssks, Apr 6, 2009.

  1. skssks

    Thread Starter New Member

    Apr 6, 2009
    Hi all,

    I have an input sine wave at 1-2 Hz at an offset (say 1-5 V).
    Generally for higher frequencies when the sine wave is severly low-passed with op-amp based circuit (with cut-off frequency very much lower than the input frequency) then the offset DC can easily obtained.
    But in this case the input frequency is only 1 Hz.

    The circuit may be filter-based or any other which can efficiently average the 1Hz sine wave.

    What circuit should I use to find the DC offset in this case ?

    Thank you,

  2. mik3

    Senior Member

    Feb 4, 2008
    Use a precision rectifier and a low pass filter with a cut-off frequency which is much lower than 1 Hz (say 50mHz).