Difficulty: Easy
Correct Answer: Correct
Explanation:
Introduction / Context:
Practical systems rarely use a single memory chip. Designers array multiple devices to meet total capacity and bus width targets. This question checks whether DRAM can be organized in banks and x-width groupings similarly to other memory families, acknowledging refresh considerations but focusing on organization principles.
Given Data / Assumptions:
Concept / Approach:
To widen the data path, place several x8 DRAMs in parallel (data lines aggregated) to create x16, x32, or x64 interfaces. To increase depth (capacity), use additional ranks/banks with separate chip selects or address multiplexing. These methods mirror how SRAM/ROM arrays are organized; the main difference is that DRAM requires periodic refresh and row/column multiplexed addressing, which the controller manages transparently.
Step-by-Step Solution:
Verification / Alternative check:
DIMMs combine many DRAM chips into modules presenting standard widths (x64 with ECC x72). Reference designs for microcontrollers show similar organization with smaller DRAMs.
Why Other Options Are Wrong:
Claiming SRAM-only is false; DRAM modules exemplify the method. Refresh cannot be disabled; it is handled, not avoided. ECC is optional and does not determine combinability.
Common Pitfalls:
Forgetting byte-lane routing and DQ/DQS alignment; overlooking rank address mapping; assuming DRAM’s need for refresh prevents standard width/capacity scaling—it does not.
Final Answer:
Correct
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