Figure 12.23 shows a master-slave edge-triggered D flip-flop. How many feedback loops are there in the circuit, and hence how many state variables? Derive excitation and output equations and construct a transition table. Identify all races and decide whether the races are critical or non-critical. Construct a state and output table and show that the circuit behaves as a positive edge-triggered flip-flop.
![973_af68841e-7f9b-4983-ba71-7ca72d91f601.png](https://secure.tutorsglobe.com/CMSImages/973_af68841e-7f9b-4983-ba71-7ca72d91f601.png)