The attached data is for the LM339. It's called a comparator, but is it the best choice?
If I understand the formula correctly, if Vcc is +12v and Vin is +5v, a good value for Vref is around 4v. Using the formula, if Rref is 100 ohms than R1 should be 200 ohms. Five resistors are needed for each of the four comparators, for a total of twenty resistors. All four of the clock kits I have that use Supertex chips just run them on +5v, with no issues. Maybe this isn't worth the trouble. Mitch On Tuesday, April 21, 2015 at 4:27:53 PM UTC-4, jrehwin wrote: > > I had an unpleasant experience about 30 years ago (yeah, before the web > existed and you had to use *printed* databooks...) with a comparator > because I failed to read the datasheet correctly. I didn't realize it had > an open-drain output, and I nearly went berserk trying to figure out why > the bloody thing's output never went high. After adding a pullup resistor I > got the output to go high, but it wasn't a nice sharp edge. > > > Ah, the LM339! I made the exact same mistake, about 18 years back. I > even wrote it up in my blog at the time: > > http://madbodger.livejournal.com/75916.html > > - John > > -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To post to this group, send an email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/aca48c66-36a9-474a-828c-b533f413c68b%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
