Physics A-Level
Johnson counter
What Johnson counter means in Physics A-Level, as defined for AQA.
Definition of Johnson counter
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Reference: AQA
Uses a shift register with the inverted last output fed back to the first input, producing a sequence of 2n states for n flip-flops.
Topics that use Johnson counter
- Sequential logic (A-level only) (AQA A-Level)
Related terms
- Asynchronous output changes
- Boolean expression
- Clock
- Clock-edge triggering
- Reset input
- Sequential logic circuits
- Timing diagram
- Truth tables
Using Johnson counter in the exam
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