Nonvolatile memory comparison: Which statement best captures the key advantage(s) of EEPROM over EPROM for in-circuit updates?

Introduction / Context:
Both EPROM and EEPROM are nonvolatile memories, but their erase and program mechanisms differ substantially. Understanding these differences helps in selecting a memory for firmware updates, calibration storage, and field serviceability.

Given Data / Assumptions:

• EPROM typically requires ultraviolet (UV) light for bulk erasure and is packaged with a quartz window or is one-time programmable (OTP) without the window.
• EEPROM uses electrical methods to erase and program data.
• Granularity and in-circuit capability are crucial selection criteria.

Concept / Approach:
EEPROM allows electrically erasing and programming at fine granularity (often byte/word) while the device remains soldered in-circuit. EPROM requires removal and exposure to UV, with bulk erasure (all contents) before reprogramming, which is inconvenient in-field. Therefore, the combined benefit—electrical erase/program at word/byte level without removal—captures EEPROM's major advantages.

Step-by-Step Solution:

Verification / Alternative check:
Datasheets specify erase times: EPROM requires minutes under UV; EEPROM writes and erases electrically in milliseconds without removal, often through I2C/SPI interfaces.

Why Other Options Are Wrong:

• EPROM UV erase faster than EEPROM: False; EEPROM updates are typically much quicker and targeted.
• Only “without removal” or only “individual words”: Each is partly true, but option (d) combines both essential advantages.

Common Pitfalls:
Confusing EEPROM with Flash; although both are electrically erasable, Flash often erases in blocks/sectors, not individual bytes/words (device dependent).

Final Answer:
the EEPROM can erase and reprogram individual words without removal from the circuit