When selecting an integrated memory chip for a digital system, which characteristics should be examined before purchase and design-in?

Introduction:
Practical hardware selection requires understanding not only how much memory you need, but also the electrical and timing behavior that ensures reliable operation on a bus or controller. This question checks awareness of data-sheet driven selection criteria.

Given Data / Assumptions:

• We are choosing a memory IC (e.g., SRAM, DRAM, Flash).
• Options include capacity, AC characteristics, and DC characteristics.
• Goal: identify whether one, some, or all properties must be considered.

Concept / Approach:

Capacity determines address space coverage. DC characteristics specify voltage levels, static currents, leakage, and input/output thresholds that determine logic compatibility and power budgeting. AC characteristics specify setup/hold times, access latency, clock-to-output delays, and timing margins essential for meeting bus frequency targets. All three are necessary to guarantee functional and reliable integration.

Step-by-Step Solution:

Verification / Alternative check:

Cross-verify with controller timing diagrams and use derating across temperature/voltage corners to ensure robustness.

Why Other Options Are Wrong:

Choosing only capacity ignores whether the device can electrically and temporally interface correctly. Selecting only AC or only DC omits the other half of the reliability equation.

Common Pitfalls:

Overlooking worst-case timing; ignoring I/O drive limits; not checking standby currents that affect battery life.

Final Answer:

all of the above