In the keypad application, just after the 4 ms mark the simulation imitates the

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Question
In the keypad application, just after the 4 ms mark the simulation imitates the release of the key by changing the column value back to F hex, which causes the d output to go into its Hi-Z state. On the next rising clock edge, what happens to dav?
Options
A. It goes HIGH.
B. It goes LOW.
C. It goes to Hi-Z.
D. It goes to 1111H.

Correct Answer

It goes LOW.

1. Which of the equations below expresses the voltage gain relationship for an operational amplifier?
Options
A. V_out = V_in/A_v
B. V_out/V_in = R_out/R_in
C. V_in/V_out = R_out/R_in
D. V_out/V_in = ?R_f/R_in

2. An actuator is usually a device that:
Options
A. converts analog data to meaningful digital data.
B. controls a physical variable.
C. stores digital data and then processes that data according to a set of specified instructions.
D. converts a physical variable to an electrical variable.

3. What function does the CTR DIV 8 circuit given below perform?
Options
A. It divides the clock frequency down to match the frequency of the serial data in.
B. The divide-by-8 counter is triggered by the control flip-flop and clock, which then allows the data output register to begin storing the input data. Once all eight data bits are stored in the data output register, the data output register and the divide-by-8 counter trigger the one-shot. The one-shot then begins the process all over again.
C. The divide-by-8 counter is used to verify that the parity bit is attached to the input data string.
D. It keeps track of the eight data bits, triggering the transfer of the data through the output register and the one-shot, which then resets the control flip-flop and divide-by-8 counter.

9. Sample-and-hold circuits in A/D converters are designed to:
Options
A. sample and hold the output of the binary counter during the conversion process
B. stabilize the comparator's threshold voltage during the conversion process
C. stabilize the input analog signal during the conversion process
D. sample and hold the D/A converter staircase waveform during the conversion process

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