74hct14 options

Archiver

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

Archiver

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

Archiver

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!