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Comparators

BritannicusBritannicus Posts: 98
edited 2011-05-31 06:20 in General Discussion
Hi there - I'm lookng for a cheap comparator IC that can work with my BS2 STAMP. My equipment pusher

I'd had the LM339 M suggested, but my kit dealer can only supply :

74HC85N
HEF4585BP
LM393M.
MC14585BCPG
MM74HC688N

Anyone tried any of these ?? - just looking at something that can compare two photoresistive circuits and give me a signal as to which is the strongest - comparing more than one would be great !

Comments

  • LeonLeon Posts: 7,620
    edited 2011-05-29 12:22
    You need an analogue comparator and most of those are digital! Check the data sheets.
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2011-05-29 12:26
    The LM393 will work.

    -Phil
  • Mike GreenMike Green Posts: 23,101
    edited 2011-05-29 12:27
    The LM393M is a low power dual analog comparator. It will produce a digital signal based on which of two inputs is at a higher voltage than the other. Look at the deta sheet for details.
  • BritannicusBritannicus Posts: 98
    edited 2011-05-31 04:55
    Cheers Guys...

    I hate to admit it, but I did download the data sheet but struggled to understand it - I shall search further for a translation as google currently seems to lack a "translate tech into dummy" function.

    failing that, now I know LM393M is a prospect ( I did wonder, but didn't trust my undertanding), I shall attempt a re-read, but somewhere that people can't see that my lips move while I'm doing it !
  • LeonLeon Posts: 7,620
    edited 2011-05-31 05:02
    Just buy a couple, Wire one up with a potential divider on one input, a pot on the other, and a DVM on the output, and see what happens when you twiddle the pot.
  • BritannicusBritannicus Posts: 98
    edited 2011-05-31 06:20
    Cheers Leon - slowly building the courage to try this out - wanting to try and build a "matchbox car" size line follower - think it would be fun to have on my office meeting table.
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