What are the input thresholds for logic 1 and 0 for TTL Look

What are the input thresholds for logic 1 and 0 for TTL? Look it up or ask your TA. What is the difference between synchronous and asynchronous inputs on sequential logic. What do you think might limit the maximum clock frequency for a flip-flop, or any sequential logic circuit for that matter? For higher clock frequencies (say 100Hz and above), the LEDs just look like they are glowing dimly. Why... what is going on? If you hooked up 10 D flip-flops in series (like you did the two flip-flops in this lab) to make a 10 bit ripple counter, how fast would the last LED blink if the input clock to the first flip-flop was a 1KHz square wave?

Solution

(2)

for TTL the input thresholds for logic 0 is 0 V to 0.8 V and input thresholds for logic 1 is 2 V to V_CC.