Look up the propagation delay from the clock to the output for the 7476. Are the HIGH-to-LOW and LOW-to-HIGH propagation delays the same?

A. Yes
B. No, [tex]t_{PLH} = 25 \, \text{ns}[/tex], [tex]t_{PHL} = 40 \, \text{ns}[/tex]
C. No, [tex]t_{PLH} = 40 \, \text{ns}[/tex], [tex]t_{PHL} = 25 \, \text{ns}[/tex]
D. No, [tex]t_{PHL} = 25 \, \text{ns}[/tex], [tex]t_{PLH} = 40 \, \text{ns}[/tex]

The HIGH-to-LOW (tPLH) and LOW-to-HIGH (tPHL) propagation delays for the 7476 are not the same; tPLH is 25 ns and tPHL is 40 ns. The correct option is b.

Explanation:

The question is about the propagation delay for the 7476, which is a TTL flip-flop integrated circuit. Propagation delay is the time it takes for a signal to travel from the clock input of a digital circuit to its output. The HIGH-to-LOW (tPLH) and LOW-to-HIGH (tPHL) propagation delays are often different due to the asymmetry in the transistor switching times within the circuit.

For the 7476 IC, the LOW-to-HIGH propagation delay is represented by tPLH and the HIGH-to-LOW propagation delay is represented by tPHL.

Therefore, the correct answer to whether the HIGH-to-LOW and LOW-to-HIGH propagation delays are the same is: B. no, tPLH = 25 ns, tPHL = 40 ns.