2. Explain about Ring and Johnson counter

Question

Accepted Answer

Ring and Johnson counters are types of shift registers used in digital electronics for counting purposes.

Ring counter is a type of shift register where the output of the last flip-flop is connected to the input of the first flip-flop, creating a ring-like structure.
Johnson counter is a type of shift register where the output of the last flip-flop is connected to the input of the first flip-flop through an XOR gate, creating a twisted ring structure.
Ring counter has 2^n states for n flip-flops, while Johnson counter has 2n states for n flip-flops.
Ring counter is used for applications where only one flip-flop should be active at a time, while Johnson counter is used for applications where multiple flip-flops can be active simultaneously.

Top SoCtronics Technologies Physical Design Engineer interview questions & answers