Connect with us

Problems with NTE 4017B IC

Discussion in 'Electronic Basics' started by Jag Man, Nov 14, 2004.

Scroll to continue with content
  1. Jag Man

    Jag Man Guest

    I am implementing a circuit proposed by Chris in which a 555 IC feeds its
    output
    to a decade counter, 4017B IC. The output of the 555 looks as expected, but
    nothing shows up at the output of the 4017. As suggested by Chris, I have
    CLK (pin 14)
    and Vss (8) at GRD, 12 VDC at Vdd (16), the output (pin 3) of the 555 going
    to
    CLKEN (13) of the 4017, and I am looking output 1 (pin 2) of the 4017. I see
    nothing on the scope.

    Any ideas as to what may be wrong? Perhaps CLKEN should be grounded and the
    input
    put to CLK?

    One thing I notice is that the NTE 4017B has a "notch" depression at one end
    and
    a "circle" depression at the other. I am assuming that pin 1 is at the end
    where the
    notch is.


    TIA

    Ed
     
  2. Since you wonder that, I wonder why you've got it wired the way you have it?
    The clock input is for the clock, the CLKEN is "clock enable". The way
    you have it, it will never count.

    Keep reset at ground, until you need to reset the counter (which in many
    applications will be never). Keep the clocke enable low, unless you want
    to disable the counting. Put the clock signal into the clock input.

    Michael
     
  3. peterken

    peterken Guest

    pin 14 is "positive" clock enable, or "positive" clock in (active high)
    pin 13 is "negative" clock enable, or "negative" clock in (active low)
    both are just "anded" internally, be it pin 13 is internally inverted, so
    both can be used as clken
    pin 8 as gnd
    pin 16 as vcc
    pin 15 is reset, set to gnd for operation

    for correct pinout and data see
    http://www.semiconductors.philips.com/acrobat_download/datasheets/HEF4017B_CNV_3.pdf
     
  4. ----------
    *ALL* input pins MUST be pulled HI or LO to make digital logic circuits
    work right, they do NOT default to some nominal value like HI or LO
    without being connected.

    -Steve
     
  5. Jag Man

    Jag Man Guest

    I was just following orders, sir. :)

    I'm a novice and a member of the group (Chris) showed it that way in the
    diagram he kindly posted.

    But, you're right. I switched them and grounded RESET and it works.

    Thanks.

    Ed
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-