Electronics-Sequential Logic Circuits
Electronics-Sequential Logic Circuits
1. A ripple counter's speed is limited by the propagation delay of:
- each flip-flop
- all flip-flops and gates
- the flip-flops only with gates
- only circuit gates
2. To operate correctly, starting a ring counter requires:
- clearing all the flip-flops
- presetting one flip-flop and clearing all the others
- clearing one flip-flop and presetting all the others
- presetting all the flip-flops
3. What type of register would shift a complete binary number in one bit at a time and shift all the stored bits out one bit at a time?
- PIPO
- SISO
- SIPO
- PISO
4. Synchronous counters eliminate the delay problems encountered with asynchronous (ripple) counters because the:
- input clock pulses are applied only to the first and last stages
- input clock pulses are applied only to the last stage
- input clock pulses are not used to activate any of the counter stages
- input clock pulses are applied simultaneously to each stage
5. One of the major drawbacks to the use of asynchronous counters is that:
- low-frequency applications are limited because of internal propagation delays
- high-frequency applications are limited because of internal propagation delays
- Asynchronous counters do not have major drawbacks and are suitable for use in high- and low-frequency counting applications.
- Asynchronous counters do not have propagation delays, which limits their use in high-frequency applications.
6. Which type of device may be used to interface a parallel data format with external equipment's serial format?
- key matrix
- UART
- memory chip
- serial-in, parallel-out
7. When the output of a tri-state shift register is disabled, the output level is placed in a:
- float state
- LOW state
- high impedance state
- float state and a high impedance state
8. A comparison between ring and johnson counters indicates that:
- a ring counter has fewer flip-flops but requires more decoding circuitry
- a ring counter has an inverted feedback path
- a johnson counter has more flip-flops but less decoding circuitry
- a johnson counter has an inverted feedback path
9. A sequence of equally spaced timing pulses may be easily generated by which type of counter circuit?
- shift register sequencer
- clock
- johnson
- binary
10. What is meant by parallel-loading the register?
- Shifting the data in all flip-flops simultaneously
- Loading data in two of the flip-flops
- Loading data in all four flip-flops at the same time
- Momentarily disabling the synchronous SET and RESET inputs