SR latch working in a laser land leveller

Discussion in 'The Projects Forum' started by kj14111996, Jun 27, 2015.

  1. kj14111996

    Thread Starter New Member

    Jun 20, 2015
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    What is the use of SR latches present on the reciever electronic board of a laser land leveller?
    The model of SR latches i am using is MC14044B.
     
  2. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
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    hi,
    We need a little more information about the leveller circuit in order to give a meaningful answer.

    A Latch can be used to hold the state of a logic signal etc ...
     
  3. kj14111996

    Thread Starter New Member

    Jun 20, 2015
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    0
    A Microcontroller IC is used to control the control box electronic board.It recieves input from the output pins of the sr latch. The latch series is a sr bar latch. S bar inputs come from the op-amp recieving signals from the photodiodes.r bar inputs are being recieved from the timer pins of the microIC.The output from the sr latch basically controls the hydraulic motors which are used to level the agricultural land. The photodiode outputs are connected to inverting inputs of op-amps respectively which when becomes low makes output high ,Rbar being anything. Now when SR latch goes to invalid state Sbar and Rbar being low(0) the output becomes 0 which is against the working logic of the leveller.
    I wanted to know is there any way out to prevent the sr latch from going to invalid state.
     
  4. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
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    OK, I follow your circuit description.

    I have used both the 4043 and 4044, never tried with both /S and /R, I will look thru the datasheet.
    E
     
  5. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
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    Checking the logic diagram shown in the 4044 datasheet, the Output cannot be Low when both inputs are Low.

    It appears that the /R pin must be being pulled Low in order to set the Output Low as the previous state of /S is a 'dont'care'

    Have you checked the /S and /R pulses on a dual channel scope.?

    E
     
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