MCQOPTIONS
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MCQOPTIONS
This section includes 1271 Mcqs, each offering curated multiple-choice questions to sharpen your Electronics & Communication Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 251. |
Which memory does not require programming equipment? |
| A. | RAM |
| B. | EPROM |
| C. | EEPROM |
| D. | UVPROM |
| Answer» B. EPROM | |
| 252. |
The circuit of the given figure performs |
| A. | OR function |
| B. | AND function |
| C. | exclusive OR function |
| D. | exclusive NOR function |
| Answer» C. exclusive OR function | |
| 253. |
In 8085 microprocessor, when TRAP interrupt is triggered program control is transferred to location |
| A. | 0020 H |
| B. | 0024 H |
| C. | 0028 H |
| D. | 002 CH |
| Answer» C. 0028 H | |
| 254. |
The following switching functions are to be implemented using a decoder f1 = ‚àëm (1, 2, 4, 8, 10, 14)f2 = ‚àëm (2, 5, 9, 15)f3 = ‚àëm (2, 4, 5, 6, 7) The minimum configuration of decoder is |
| A. | 2 to 4 line |
| B. | 3 to 8 line |
| C. | 4 to 16 line |
| D. | 5 to 32 line |
| Answer» D. 5 to 32 line | |
| 255. |
To convert JK flip flop to D flip flop |
| A. | connect D to both J and K |
| B. | connect D to J directly and D to K through inverter |
| C. | connect D to K directly and D to J through inverter |
| D. | connect D to K and leave J open |
| Answer» C. connect D to K directly and D to J through inverter | |
| 256. |
Which one of the following can be used as parallel to series converter? |
| A. | Multiplexer |
| B. | Demultiplexer |
| C. | 2.5 μ sec |
| D. | 25 μ sec |
| Answer» D. 25 Œº sec | |
| 257. |
Which of the following is a self-complementing code? |
| A. | 8421 code |
| B. | Excess 3 codes |
| C. | Pure binary code |
| D. | Gray code |
| Answer» E. | |
| 258. |
Assertion (A): An encoder converts key dips to binary code.Reason (R): An encoder has more inputs than output. |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is true, R is false |
| D. | A is false, R is true |
| Answer» C. A is true, R is false | |
| 259. |
Digital circuits mostly use |
| A. | Diodes |
| B. | Bipolar transistors |
| C. | Diodes and bipolar transistors |
| D. | Bipolar transistors and FETs |
| Answer» D. Bipolar transistors and FETs | |
| 260. |
A/D parallel converter is also called flash converter. |
| A. | 1 |
| B. | |
| C. | (16)16 |
| D. | (2)2 |
| Answer» B. | |
| 261. |
Find the output voltage for 011100 in a 6 bit R-2R ladder D/A converter has a reference voltage of 6.5 V. |
| A. | 6.4 V |
| B. | 2.84 V |
| C. | 0.1 V |
| D. | 8 V |
| Answer» C. 0.1 V | |
| 262. |
D/A converters are generally |
| A. | weighted resistor network |
| B. | binary ladder network |
| C. | either (a) or (b) |
| D. | neither (a) nor (b) |
| Answer» C. either (a) or (b) | |
| 263. |
While obtaining minimal SOP expression |
| A. | all do not care terms are treated as 0 |
| B. | only such do not care terms which aid minimization are treated as 1 |
| C. | 6 |
| D. | 8 |
| Answer» E. | |
| 264. |
What is the terminal count in decimal form? |
| A. | 1579 |
| B. | 1681 |
| C. | 1881 |
| D. | 2014 |
| Answer» B. 1681 | |
| 265. |
Y = A + A B is the same as |
| A. | Y = AB |
| B. | Y = A + B |
| C. | Y = A + B |
| D. | Y = A + B |
| Answer» C. Y = A + B | |
| 266. |
Suppose a microprocessor has memory locations from 0000 to 3FFF, each storing I byte. How many bytes the memory can storing I bytes the memory can store? |
| A. | 4384 |
| B. | 8644 |
| C. | 12688 |
| D. | 16384 |
| Answer» C. 12688 | |
| 267. |
For emitter-couple logic, the switching speed is very high because |
| A. | negative logic is used |
| B. | the transistors are not saturated when conducting |
| C. | emitter-coupled transistors are used |
| D. | multi-emitter transistors are used |
| Answer» C. emitter-coupled transistors are used | |
| 268. |
Thu advantage of using a dual stop ADC in a digital voltmeter is that |
| A. | its conversion time is small |
| B. | its accuracy high |
| C. | output is in BCD format |
| D. | it does not require a comparator |
| Answer» C. output is in BCD format | |
| 269. |
The Boolean expression for the shaded area in the Venn diagram is |
| A. | X + Y + Z |
| B. | XY + Z + X YZ |
| C. | X Y Z + XY |
| D. | X + Y + Z |
| Answer» D. X + Y + Z | |
| 270. |
Decimal 8 in excess-3 code = |
| A. | 1000 |
| B. | 1001 |
| C. | 1011 |
| D. | 1111 |
| Answer» D. 1111 | |
| 271. |
PROM is |
| A. | Permanent Read Only Memory |
| B. | Polarized Read Only Memory |
| C. | Positive Read Only Memory |
| D. | Programmable Read Only Memory |
| Answer» E. | |
| 272. |
The converter whose conversion time is independent of number of bits is |
| A. | dual stope |
| B. | counter type |
| C. | parallel conversion |
| D. | successive approximation |
| Answer» D. successive approximation | |
| 273. |
In the decimal number 27, the digital 2 represents |
| A. | 2 |
| B. | 20 |
| C. | 0.2 |
| D. | 200 |
| Answer» C. 0.2 | |
| 274. |
Unlimited number of ICs 7490, 78492 and 7493 are available. Which of these could be used to build the dividse-by-60 circuit of figure |
| A. | 7490 |
| B. | 7492 |
| C. | combination of 7490 and 7492 |
| D. | combination of 7492 and 7493 |
| Answer» D. combination of 7492 and 7493 | |
| 275. |
In D-type FF, Preset (Pr) and clear (Clr) inputs are called |
| A. | Synchronous |
| B. | Asynchronous |
| C. | Data |
| D. | None |
| Answer» C. Data | |
| 276. |
In a flip flop which input determines the state to which output will transistion? |
| A. | Control input |
| B. | Clock input |
| C. | Both control and clock input |
| D. | Either control or clock input |
| Answer» B. Clock input | |
| 277. |
The Boolean function A + BC is a reduced form of |
| A. | AB + BC |
| B. | (A + B) . (A + C) |
| C. | AB + ABC |
| D. | (A + C) . B |
| Answer» D. (A + C) . B | |
| 278. |
In a digital counter the number of flip-flops is |
| A. | always 2 |
| B. | always even |
| C. | always odd |
| D. | equal to the number of bits required in the final binary count |
| Answer» D. equal to the number of bits required in the final binary count | |
| 279. |
The number of FF required for a divide by 12 circuit is |
| A. | 16 |
| B. | 12 |
| C. | 8 |
| D. | 4 |
| Answer» E. | |
| 280. |
How many input-output ports can be accessed by direct method of 8085 μp? |
| A. | 32 K |
| B. | 64 K |
| C. | 1000000000000 |
| D. | 10000000000000 |
| Answer» C. 1000000000000 | |
| 281. |
A counter has N flip flops. The total number of states are |
| A. | N |
| B. | 2 N |
| C. | 2N |
| D. | 4 N |
| Answer» D. 4 N | |
| 282. |
TRAP is __________ whereas RST 7.5, RST 6.5, RST 5.5 are __________ . |
| A. | maskable, non-maskable |
| B. | maskable, maskable |
| C. | non-maskable, non-maskable |
| D. | non-maskable, maskable |
| Answer» E. | |
| 283. |
An encoder converts decimal numbers to binary and other codes. |
| A. | 1 |
| B. | |
| C. | (X + Y) (X + Y) |
| D. | (X + Y) (X + Y) |
| Answer» B. | |
| 284. |
Which liquid crystal is used for LCD display? |
| A. | Mercury |
| B. | Pneumatic fluid |
| C. | Aqua regia |
| D. | Liquid boron |
| Answer» C. Aqua regia | |
| 285. |
The open wired circuit in the given figure works as a |
| A. | EX - NOR gate |
| B. | AND gate |
| C. | XOR gate |
| D. | NOR gate |
| Answer» D. NOR gate | |
| 286. |
Which of the following is susceptible to race condition? |
| A. | R-S latch |
| B. | D latch |
| C. | Both R - S and D latches |
| D. | None of the above |
| Answer» B. D latch | |
| 287. |
When a bit is 0 is a DDR, it makes the corresponding port pin an __________ On the other hand, a 1 bit programs a __________ Pin. |
| A. | output, input |
| B. | output, output |
| C. | input, input |
| D. | input, output |
| Answer» E. | |
| 288. |
The generic microprocessor contains a zero and a carry flag. These are located on theThe 8156 of a figure has RAM locations from 2000 H to 20 FFH. |
| A. | interrupt control |
| B. | status register |
| C. | either (a) or (b) |
| D. | none of the above |
| Answer» C. either (a) or (b) | |
| 289. |
Assertion (A): In a serial in-serial out shift register, access is available only to the left most or right most flip flops Reason (R): If the output of a shift register is feedback to serial input it can be used as a ring counter. |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is true, R is false |
| D. | A is false, R is true |
| Answer» C. A is true, R is false | |
| 290. |
Point out the wrong statement, Sequential logic circuit is |
| A. | one that requires a clock to change states |
| B. | one in which past affects the present states |
| C. | one whose outputs changes immediately when the inputs change |
| D. | also called clock logic or synchronous logic |
| Answer» D. also called clock logic or synchronous logic | |
| 291. |
figure shows a NAND latch used as a switch debouncer. With the switch in STOP position. Q will be equal to |
| A. | 0 |
| B. | 1 |
| C. | CLK |
| D. | none of these |
| Answer» B. 1 | |
| 292. |
Which of them contains an organic fluid? |
| A. | LED |
| B. | LCD |
| C. | Both LED and LCD |
| D. | Neither LED nor LCD |
| Answer» C. Both LED and LCD | |
| 293. |
In a positive-edge-triggered JK flip-flop, a low J and a low K produce __________ state. A high __________ on the rising edge of the clock. |
| A. | active, toggle |
| B. | inactive, toggle |
| C. | very fast |
| D. | fast |
| Answer» E. | |
| 294. |
For the logic circuit given, what is the simplified Boolean function? |
| A. | X = AB + C |
| B. | X = BC + A |
| C. | X = AB + AC |
| D. | X = AC + B |
| Answer» C. X = AB + AC | |
| 295. |
As the number of flip flops are increased, the total propagation delay of |
| A. | ripple counter increases but that of synchronous counter remains the same |
| B. | both ripple and synchronous counters increase |
| C. | both ripple and synchronous counters remain the same |
| D. | ripple counter remains the same but that of synchronous counter increases |
| Answer» B. both ripple and synchronous counters increase | |
| 296. |
In the CMOS inverter |
| A. | one transistor is N channel and the other P channel |
| B. | one is enhancement type and other depletion type |
| C. | both are N channel with one enhancement and the other depletion type |
| D. | none |
| Answer» C. both are N channel with one enhancement and the other depletion type | |
| 297. |
The circuit show in the figure has 4 boxes each described by inputs P, Q, R and outputs y, z withY = P ‚äï Q ‚äï R, Z = RQ + PR + QP The circuit act as a |
| A. | 4 bit adder giving P + Q |
| B. | 4 bit subtractor P - Q |
| C. | 4 bit subtractor Q - P |
| D. | 4 bit adder P + Q + R |
| Answer» C. 4 bit subtractor Q - P | |
| 298. |
The factors which govern fan out of CMOS gates are |
| A. | maximum permissible propagation delay |
| B. | input capacitance of each load |
| C. | both (a) and (b) |
| D. | neither (a) nor (b) |
| Answer» D. neither (a) nor (b) | |
| 299. |
The decimal equivalent of the hexadecimal number (3 E 8)16 is |
| A. | 1000 |
| B. | 982 |
| C. | 768 |
| D. | 323 |
| Answer» B. 982 | |
| 300. |
Which device uses Pneumatic fluid? |
| A. | LED |
| B. | LCD |
| C. | VF display |
| D. | None of these |
| Answer» C. VF display | |