Configurable Logic Circuit Some newer PICs come with this circuit block. There are, I think, 8=20 inputs that can come from a variety of sources both internal and=20 external. Basically, something like a single-cell CPLD. The really cool feature is that stuff happens at hardware speeds, not=20 software. Directly coupling the comparitor into this logic cell=20 allows very fast response to external events. Even Microchip's tiniest full-featured chip: the 6-lead 10F322 has=20 this block. Unfortunately, they didn't include a comparitor on the=20 chip. Sadly, that eliminates this particular chip from a lot of=20 projects that I would otherwise use it in. dwayne At 03:55 PM 5/9/2014, Bob Axtell wrote: >what do you mean by "CLC"? > >--Bob A >-- >On 5/9/2014 2:46 PM, Dwayne Reid wrote: > > At 07:59 PM 5/8/2014, Phil Keller wrote: > >> I have been looking at the 16F170x series and I am at a loss as far as > >> the CLC functionality. It is "Cool" but I am having a tough time comi= ng > >> up with an application that would take advantage of it. Are there som= e > >> real world designs (without giving away trade secrets) that have used > >> this capability or is this a solution looking for a problem? > > I haven't used the CLC for this yet, but I have one product in > > production that uses the on-board S-R latch in the PIC16F677. The > > 'Set' input of the latch is set in software but the 'Reset' pin is > > driven directly by the on-board comparitor. This comparitor is > > monitoring the peak current consumed by the load (large DC motor) and > > this hardware configuration gives me as close to instantaneous > > shutdown as is possible when an over-current fault occurs. The trip > > time is significantly faster than would have been possible by using > > an interrupt / software. > > > > This chip (PIC16F6xx) was created before the CLC existed. If I were > > doing a similar project today, I'd definitely use the CLC for=20 > this function. > > > > This (very) fast hardware shutdown has saved many large FETs from an > > untimely demise and completely eliminated the field failures caused > > by 'Oopses' where the motor leads were shorted accidently. > > > > dwayne > > > >-- >http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive >View/change your membership options at >http://mailman.mit.edu/mailman/listinfo/piclist --=20 Dwayne Reid Trinity Electronics Systems Ltd Edmonton, AB, CANADA (780) 489-3199 voice (780) 487-6397 fax www.trinity-electronics.com Custom Electronics Design and Manufacturing --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .