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74hct14 options

ArchiverArchiver Posts: 46,084
edited 2000-07-14 23:08 in General Discussion
I currently have a single ir wheel encoder (SY124) hooked to a Stamp II
input. I am using a 74hct14 to clean up the signal from the encoder. I
was wondering if anyone had a suggestion on cleaning up the signal with
something else. The chip takes up a lot of space for using only one
logic segment.

Thanks,
Rick

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2000-07-14 19:40
    At 11:01 AM 7/14/00 -0700, you wrote:
    >I currently have a single ir wheel encoder (SY124) hooked to a Stamp II
    >input. I am using a 74hct14 to clean up the signal from the encoder. I
    >was wondering if anyone had a suggestion on cleaning up the signal with
    >something else. The chip takes up a lot of space for using only one
    >logic segment.
    >
    >Thanks,
    >Rick
    >

    Fairchild Semiconductor makes a NC7S14
    (www.fairchildsemi.com/ds/NC/NC7S14.pdf), which is a single schmitt trigger
    inverter in a package. It comes in both 5 pin SOT-23 and 5 pin SC70
    packages. Digikey (www.digikey.com) carries the SOT-23 version.

    Bob Baxter
  • ArchiverArchiver Posts: 46,084
    edited 2000-07-14 23:08
    Rick,

    If there's some reason you don't want to use one of those single-gate SMT
    logic chips, you can do this job with a comparator or a spare non-inverting
    logic gate, using external resistors to apply a little positive feedback.
    Schmidt trigger circuits can also be assembled from a few discrete
    components-- see any sixties era transistor circuit cookbook.

    >I currently have a single ir wheel encoder (SY124) hooked to a Stamp II
    >input. I am using a 74hct14 to clean up the signal from the encoder. I
    >was wondering if anyone had a suggestion on cleaning up the signal with
    >something else. The chip takes up a lot of space for using only one
    >logic segment.

    Mike Hardwick, for Decade Engineering -- <http://www.decadenet.com>
    Manufacturer of the famous BOB-II Serial Video Text Display Module!
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