For fixed frequency operation there's always Wenzel's divider using a D FF with LC feedback: http://www.wenzel.com/wp-content/uploads/dividers.pdf At least the power consumption is low.
Bruce > On 03 July 2020 at 12:35 Bob kb8tq <kb...@n1k.org> wrote: > > > Hi > > > On Jul 2, 2020, at 6:38 PM, jimlux <jim...@earthlink.net> wrote: > > > > On 7/2/20 2:50 PM, Bob kb8tq wrote: > >> Hi > >>> On Jul 2, 2020, at 5:30 PM, jimlux <jim...@earthlink.net> wrote: > >>> > >>> On 7/2/20 11:37 AM, ed breya wrote: > >>>> It's been fun reminiscing about all these dividers and techniques, but > >>>> getting back to the OP, the original search was for a divide by 5 with > >>>> "low power" and operation from 5 to possibly 3.3V, and clocking properly > >>>> at 50 MHz. One would assume also minimal size and complexity, and low > >>>> cost. > >>> > >>> You forgot to add rad-hard.. I was the OP - This has been a fascinating > >>> thing - we have a breadboard that uses a fancy clock distribution chip > >>> that consumes close to a watt (and has too much jitter, as well).. > >> > >>> 3) It's hard to even find programmable logic that is simple and small. > >>> All the mfrs tout their latest tiny parts with *only half a million > >>> gates* (I exaggerate, but you get the picture) > >> If they want to sell you a fully self contained "million gate" device for > >> a couple bucks, is that really > >> a bad thing? Sure, if it’s in a thousand pin BGA, it’s a bad thing. If > >> it’s in a < 40 pin package that > >> you can get on a small board …. maybe not so much. > > > > yes, if it's in a small pinout package. One other peculiarity that I've > > been burned by is that a lot of the modern devices with large logic and few > > I/O pins have power dissipations that are clock rate independent for the > > internal logic - it's the leakage current that dominates and that's VERY > > dependent on die temp. > > > > > > I think though, that the marketplace is driving towards increased > > functionality on one chip, with bigger die size. Those of us who want 50 > > gates at medium or low speed are distinctly in the minority. > > There are very few applications that require that sort of device. Volume > matters ( a lot !!) > > Bob > > > > > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts@lists.febo.com > > To unsubscribe, go to > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
