Discussion in 'General Electronics Chat' started by hami007, Jun 10, 2009.

  1. hami007

    Thread Starter Member

    Oct 26, 2008
    hi i want to use two 4017 in cascade such that first 4017 ic count up to ten then second 4017 ic will be enabled and first one would be disabled when second 4017 ic complete its count then first 4017 ic will be eabled again and so on
    can any one help
  2. Wendy


    Mar 24, 2008
  3. prashprad

    New Member

    Jun 18, 2009
    Can any output from the 4017 be made momentary ON. I am constructing a circuit where I use a monostable as a 1 second clock triggered by a reed switch, for my decade counter to produce 7 sequential counts after which it resets since pin 6 is connected to pin 15.
    Therefore each trigger of the reed advances the counter by one until the 7th trigger makes pin 5 ON. Only when the 8th pulse comes in will the counter reset the count cycle and therefore Output 6 (pin 5) remains ON.
    I want to use this output and convert this to a momentary pulse ie. pin 5 should act like a momentary switch or atleast be able to use the output to drive a device that momentarily enables a relay or other device.
    I tried using a monostable at the output of the counter, however the trigger input of the monostable needs to be momentary and connecting the counter pin 5 to the trigger pin 2 of the 555 (1 second timer) keeps prevents the timer from oscillating and holds it output. Unless the pulse at pin 2 of the 555 is momentary, it does not behave like a timer.
    Any suggestions how to achieve a momentary output from a decade counter.
  4. Audioguru

    New Member

    Dec 20, 2007
    I use logic gates to make the outputs of my Ultra-Bright Chasers blink each LED for a very short duration even though the outputs of the 74HC4017 are turned on for a much longer duration. The the project saves a lot of battery power so its two AA alkaline cells last for months.