DE paper

The binary numbering system has

• 10 distinct states

• 2 distinct states

• 8 distinct states

• 16 distinct states

Fig 7 shows a switch representation of a logic function. What is the equivalent logic gate function?

• OR gate

• NOT gate

• NOR gate

• NAND gate

An 8 Mhz square drives a 4-bit binary counter. What is the frequency of the waveform at the output of the last flip-flop of the counter?

• 250 kHz

• 500 kHz

• 1 MHz

• 1.6 MHz

The output of a 2-input NOR gate is HIGH if

• either input is LOW

• either input is HIGH

• both inputs are LOW

• both inputs are HIGH

When constructing the 2-input NOR function by using NAND gates only, how many NAND gates are minimally required?

• one.

• two.

• three.

• four.

Derive the Boolean expression for the logic circuit shown in the figure.

The JK flip-flop will perform a toggle operation when

• J=0, K=0.

• J=0, K=1.

• J=1, K=0.

• J=1, K=1.

How many flip-flops are required to construct a MOD-64 binary counter?

• four

• five

• six

• seven

If a 5-bit asynchronous up counter has an initial count of 00100, what will be its value after 21 clock pulses?

• 11001

• 11010

• 11011

• 11100

Figure shows a 7-Segment display unit. Which of the 7-segment LED must be lit in order to display a digit '2'?

• a,b,d,e, and g segments

• a,b,c,d, and g segments

• b,d,e,f and g segments

• c,d,e,f and g segments