OFF-the-wall idea for momentary ON switch

MrDEB

Well-Known Member
Looking to build a digital kitchen timer that shuts off after timing out and/or a 10 second delay waiting for user input.
Here is the screenshot of the on/off section of the kitchen timer. Going to use an 18Fxxxx pic
maybe need a diode on the pic output pin to prevent applying voltage to the unpowered pic. unpowered pic?
 
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So you completely ignored my comments in post #16 regarding the latch circuits, and the comments in post #17 about the LCD backlight and now the LCD itself being always on? Oh, and the comment regarding LCD control lines?

At least your schematic can be read now.

Well, I tried.
 
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took a second look at circuit #4 maybe
My posted schematic has a major flaw so here is new corrected schematic but will research circuit#4 again
 

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taking a second look at the circuits in post#12 and discovered these two schematics BUT my schematic in post#22 looks like a lot less parts?
both of these are from youtube electronoobs.com
 

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MrDEB said:
BUT my schematic in post#22 looks like a lot less parts?
Click to expand...

Well, you can do whatever you like. The options I have suggested have been demonstrated to work. They also allow you to adjust the delay time in firmware. Or use what you've got, with a fixed delay in hardware. Perhaps it will work.

I don't like the idea of switching the ground connection, but that just my personal preference. It probably won't be a problem.
 
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BTW, your circuit isn't going to work for any number of reasons (some of which have already been ignored) but specifically because the ground pins of micro are not properly connected to the mosfet.
 
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and the comments in post #17 about the LCD backlight and now the LCD itself being always on?
Click to expand...
still ignored.

Is the LCD backlight even going to turn on? You've got it arranged to only supply about 15mA.
Maybe I missed it somewhere, but where's the "5V" come from?
 
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For The Popcorn said:
Considering the audience, do you really think this is a good suggestion?
Click to expand...
Life is easier when you realize the advice you give is just as valuable as the background education you provide that answers why the advice you give is correct. And, life is more fun (and easier) when you don't give a crap if they follow your advice or not - that is - unless you view each of your posts as a "win" or a "loss". In that case, you shouldn't bet on yourself. Your advice seem to be ignored quite frequently based only on the number of times you complain about it being ignored.
 
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I have not IGNORED popcorn's advice. Just because I looked at his links on youtube doesn't mean I ignored his links.
And yes, I have removed the extra cap I had in my schematic (c2) but no mention about the caps I added as popcorns suggestions. Am hoping to breadboard the delay circuit I have within my schematic. Curious if a Mosfet would work better than the NPN transistor in my delay circuit?
 
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You may want to rename your "switched ground" and actual ground to prevent confusing them. Everything past the MOSFET should probably connected to "switched ground".
 
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Maybe you've not been around long enough to appreciate some of the help that has been given to MrDEB. Here's a thread from 2009 that I tried to help in by posting full working code (on page 2).

Mike
 
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Pommie said:
Maybe you've not been around long enough to appreciate some of the help that has been given to MrDEB. Here's a thread from 2009 that I tried to help in by posting full working code (on page 2).

Mike
Click to expand...
Maybe I have been around long enough to see that members keep giving him advice that he doesn't follow and then scold him for not following the advice. My advice to members who complain is, stop trying to help him.

Now, should I complain after your next post on this thread because you weren't following my advice?
 
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