How Do I Build a Logic Gate for a Voting System?

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JosephF
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Homework Statement



I'm studying logic gates and trying to create my first one.

Homework Equations



3. In a TV programme, the panel votes on new performers.
The panel consists of a Chairman (C) and three others (X, Y and Z) who each press a button to register their vote.

The SUCCESS light is switched on if:
Either The Chairman and at least one of the panellists vote yes
Or All three panellists vote yes

Otherwise the FAIL light is switched on.

Design a logic circuit which correctly switches each light on according to the voting of the panel.

The Attempt at a Solution



I've written all the statements our and managed to derive:

S = C AND (X OR Y OR Z) OR (X AND Y AND Z)

Which I think is correct. I'm now not sure where to go from here. I've googled but can't find any think relevant.

Regards,
 
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JosephF said:

Homework Statement



I'm studying logic gates and trying to create my first one.

Homework Equations



3. In a TV programme, the panel votes on new performers.
The panel consists of a Chairman (C) and three others (X, Y and Z) who each press a button to register their vote.

The SUCCESS light is switched on if:
Either The Chairman and at least one of the panellists vote yes
Or All three panellists vote yes

Otherwise the FAIL light is switched on.

Design a logic circuit which correctly switches each light on according to the voting of the panel.

The Attempt at a Solution



I've written all the statements our and managed to derive:

S = C AND (X OR Y OR Z) OR (X AND Y AND Z)

Which I think is correct. I'm now not sure where to go from here. I've googled but can't find any think relevant.

Regards,

I think you will want to be clear with your grouping.

S = (C Λ (X V Y V Z)) V ( X Λ Y Λ Z)
 
Ah yes, that looks better.

Whats my next step? Do I need to input it into a truth table or do I go streight to the logic gates? Also, can and AND statement have more than 2 inputs?

Thanks,
 
JosephF said:
Ah yes, that looks better.

Whats my next step? Do I need to input it into a truth table or do I go streight to the logic gates? Also, can and AND statement have more than 2 inputs?

Thanks,

Sure you can put as many inputs into an And or Or or Nand or Nor as you want.

Unless you are asked for a Truth Table ... why bother?