Sequential Logic
Circuits with feedback
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Sequential Logic
Simplest circuits with feedback: latch
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What We Need:
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What We Need:
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Sequential Logic
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Sequential Logic
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Let’s Use This Latch
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Sequential Logic
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Sequential Logic
5
Sequential Logic
6
Let’s Use This D flip-flop
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Registers
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Sequential Logic
7
Example - Circuit with Feedback
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Sequential Logic
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Sequential Logic
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Examples (cont’d)
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Sequential Logic
9
Example - Circuit without Feedback
Timing Methodologies (cont’d)
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Sequential Logic
11
Sequential Logic
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Typical timing specifications
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Synchronous System Model
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Combinational
Logic
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Sequential Logic
System Clock Frequency
Shift register
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Sequential Logic
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Combinational
Logic
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reg tpd
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C.L. tpd
Sequential Logic
15
4-bit Universal shift register
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Sequential Logic
Design of Universal Shift Register
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Sequential Logic
17
Sequential Logic
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Binary counter
Other Counters: cheaper/faster
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Sequential Logic
19
Sequential Logic
20