GATE EC 2018 Set 1 — Question 42
Go beyond PYQs with Success TrackerAI-powered personalised practice and doubt support. Unlimited practice on eligible plans; AI usage limits apply.MCQ+2 / -0.67MediumROM, PROM, EPROM & EEPROMSemiconductor MemoriesDigital Circuits
Digital Circuits → Semiconductor Memories → ROM, PROM, EPROM & EEPROM
Last updated
Question
A ROM array is built with the help of diodes as shown in the circuit below. Here and are signals that select the word lines and and are signals that are output of the sense amps based on the stored data corresponding to the bit lines during the read operation.
During the read operation, the selected word line goes high and the other word line is in a high impedance state. As per the implementation shown in the circuit diagram above, what are the bits corresponding to (where or and or ) stored in the ROM?
Correct answer
(A) [figure] ]
Solution
In a diode-based ROM array, the presence of a diode at the intersection of a word line and a bit line represents a logic '1' being stored, while the absence of a diode represents a logic '0'.When word line is selected (goes high):
- There is a diode at the intersection of and . Thus, will be high (1). So, .
- There is no diode at the intersection of and . Thus, will remain low (0). So, .
- There is no diode at the intersection of and . Thus, will remain low (0). So, .
- There is a diode at the intersection of and . Thus, will be high (1). So, .
Continue learning with Success Tracker
A step still unclear? Work through it with support
Use Success Tracker to ask about the reasoning, then try another GATE EC question to check your understanding.
AI-powered practice· Unlimited practice on eligible plans
- PYQs with solutions
- Attempt available previous-year questions, then compare your reasoning with the worked solution. Coverage varies by stream.
- Practice that adapts
- Choose a topic, work on weaker areas and bookmark questions to revisit. Your attempts feed your progress tracking.
- AI doubt support
- Ask follow-up questions about a step or concept while practising, instead of stopping at the final answer.
Unlimited practice is available on eligible plans. Free practice and AI usage have limits; check the current plan allowances before choosing.
This page stays readable without an account. AI responses can be wrong; check them against the solution and source material.
More questions on Semiconductor Memories
2026 Set 1 Q20In the circuit shown in the Figure, A and B are logic inputs and Y is the logic output. Which of…2026 Set 1 Q27A binary ripple counter is designed to count to . Which of the following…2026 Set 1 Q35The negative edge triggered JK flip-flop in the Figure has J and K inputs tied to Logic High and a…2026 Set 1 Q42The address of the first location of a 256 kilo byte (KB) memory is . Choose the correct…2026 Set 1 Q45What is the complement of ?