# Frequency divider by 2 with COMBINATIONAL logic

Discussion in 'Homework Help' started by EngIntoHW, Sep 4, 2010.

1. ### EngIntoHW Thread Starter Member

Apr 24, 2010
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Hey,

I was asked to design a frequency divider by 2, with COMBINATIONAL logic.

You have an idea how it could be done?

I thought of this:
What do you say?

(I forgot to mention it in the schematics, the output of the circuit is O0)

Thank you.

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Last edited: Sep 4, 2010
2. ### t_n_k AAC Fanatic!

Mar 6, 2009
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Are there any restrictions on the logic elements you are allowed to use?

3. ### EngIntoHW Thread Starter Member

Apr 24, 2010
128
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Hi t_n_k,

no, there're no restrictions.

I added above a proposed solution.

Mar 6, 2009
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5. ### EngIntoHW Thread Starter Member

Apr 24, 2010
128
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doesn't that circuit in vlsibank double the frequency by 2? (not divides)

6. ### t_n_k AAC Fanatic!

Mar 6, 2009
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782
The topic in the link was ...

"Clock divider without using flip-flops"

7. ### EngIntoHW Thread Starter Member

Apr 24, 2010
128
0
Hi,

Edit:

I got you, thanks a lot t_n_k

Last edited: Sep 4, 2010
8. ### Ghar Active Member

Mar 8, 2010
655
72
This seems like a silly exercise because as soon as you start adding feedback it technically isn't combinational anymore... the definition of combinational is that it does not depend on any past values.

A flip flop can be made of just logic gates yet it isn't considered combinational.

By definition this requires sequential logic... the thread t_n_k found is a much more accurate statement.

So anyway, that's enough useless nitpicking for now.