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Logic problem - will flip flops or multivibrators work?

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rancorguy

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glops problem

There are 5 inputs and outputs.
When an input goes high, its output goes high.
But, when the most current input to goes high along with its output, all other outputs have to go low even if their respective inputs are still high.

Ex: Step 1: Input 1 high = output 1 high
Step 2: Input 4 high = output 4 high, output 1 low (input 1 still high)
Step 3: Input 2 high = output 2 high, output 1 and 4 low (input 1 and 4 still high)
Step 4: Input 4 low = no change

Doesn't depend on order that the inputs are acted on, just which one is high last.

This is using all solid state electronics, so no moving parts. I have never used a flip-flop in an analog circuit before, so I don't know if it would work in this case. I know they need a clock, but am not sure on how to get that to work. I was also looking up information about multivibrators, but have never used those either. I'm just confused on how to even get started on this.
 

logic circuit flip-flops problems

If you have input 1 high, and then set input 1 low, will output 1 go low, or will it remains high?

I was thinking out some pls shema when this obvious question put it to end.
 

logic flip flop work

Yes, if input 1 is high and then is set low, output 1 will also go low.
 

how do multi vibrators work

Trying to figure out something, but don't get a good solution. But my way is to use reset-dominant SR flipflops and a lot of OR-gates that takes input from three of the SR-flipflops and leads to the reset input of the last SR-flipflop. For all four SR's. Inputs goes to each SR's main input.
 

flip flop circuit how to 1 input 4 output

I went the route of trying simple gates and SR latches at first, but like you I wasn't getting anywhere and just creating a bunch of circuits that either oscillated or just didn't do the right thing. So, I was trying to see if there were any other ways that it could be done. I had talked to someone and they mentioned multivibrators and flip-flops, but I've never used those in an analog circuit.

Added after 2 hours 59 minutes:

Is this what you were saying or did I misunderstand you?

This doesn't work, and I'll post later another drawing of a different idea that I'd like some feedback on.

Thanks everyone :)
 

I'm not sure why this is posted to the Analog Cicuit Design forum since it is obviously a Digital domain problem. However, this could very easily be handled by a small, low-cost microcontroller and a very small amount of code.

There are any number of controllers that could be used. For example, Microchip's PIC16F688 has just 14 pinws, an internal oscillator, draws very little power, is available in several different packages, and cost about $1.60 in single quantities. You won't need to add any other components other than a bypass capacitor.
 

It is here because it is part of a solid state analog circuit. Also, there is going to be no programming involved. I know it's a lot easier to just use a micro-controller, but I can't so I have to figure out another way to do it.
 

Here's another idea....


Any input or suggestions would be greatly appreciated :)

Left out one connection from pin 3 of U8 to Reset of U3A. oops ;)
 

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