The time interval on the leading edge of a pulse between 50% and 50% of the amplitude is the ( ).
A. rise time
B. fall time
C. pulse width
D. period
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A quantity having continuous value is ( ).
A. a digital quantity
B. an analog quantity
C. a binary quantity
D. a natural quantity
A nonretriggerable one-shot with an active HIGH output has a pulse width of 20ms and is triggered from a 60 Hz line. The output will be a ()
A. series of 16.7 ms pulses
B. series of 20 ms pulses
C. constant LOW
D. constant HIGH
The modulus of a counter is ()
A. the number of flip-flops
B. the actual number of states in its sequence
C. the number of times it recycles in a second
D. the maximum possible number of states
The 74138 is a 3-to-8 decoder. Together, two of these ICs can be used to form one 4-to-16 decoder. To do this, connect ()
A. one decoder to the LSBs of the input; the other decoder to the MSBs of the input
B. all chip-select lines to ground
C. all chip-select lines to their active levels
D. one chip-select line on each decoder to the input MSB
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