In DRAM devices, the approximate power requirements in active mode and in standby mode are respectively:

Difficulty: Easy

Correct Answer: 350 mW and 5 mW respectively

Explanation:


Introduction:
Dynamic RAM (DRAM) consumes significantly more power during active access (row/column activation, refresh) than when placed in standby/idle modes. This question checks recognition of the order-of-magnitude difference between active and standby power.


Given Data / Assumptions:

  • Legacy/general DRAM power figures.
  • Relative comparison across modes rather than a specific vendor part.


Concept / Approach:

Active DRAM cycles involve wordline and bitline charging/discharging plus sense amplifiers and refresh logic, leading to higher mW consumption. In standby, only retention/refresh and minimal biasing are maintained, drastically reducing power.


Step-by-Step Solution:

Step 1: Recall representative figures: hundreds of mW active vs. a few mW standby for classic parts.Step 2: Compare options; only one shows a large gap from hundreds of mW to single-digit mW.Step 3: Select '350 mW and 5 mW respectively' as the closest standard textbook pair.


Verification / Alternative check:

Vendor datasheets historically list active power in the several-hundred mW range and standby in the few-mW to tens-of-mW range depending on density and process.


Why Other Options Are Wrong:

'350 mW each' and '5 mW each' ignore mode-dependent differences; '350 mW and 100 mW' understates the standby reduction.


Common Pitfalls:

Assuming standby equals zero; overlooking self-refresh vs. active-refresh nuances, which still remain far below active power.


Final Answer:

350 mW and 5 mW respectively

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