Fixed regulators by number For a standard 78xx series linear regulator, what regulated DC output does a 7814 provide under proper operating conditions?

Introduction / Context:The 78xx family are positive fixed-output linear regulators used in countless power supplies. The “xx” suffix indicates the nominal output voltage. Knowing these at a glance speeds up design and troubleshooting when scanning a board or a parts bin.

Given Data / Assumptions:

• Device is a 7814 from the 78xx family.
• Proper input voltage headroom and heat sinking are assumed.
• Standard pinout and positive regulation behavior apply.

Concept / Approach:

For 78xx regulators, “xx” corresponds to the output voltage in volts. Examples: 7805 → +5 V, 7812 → +12 V, 7815 → +15 V. Therefore, 7814 provides a regulated +14 V DC output. The companion negative series are 79xx (e.g., 7912 for –12 V), not to be confused with 78xx.

Step-by-Step Solution:

Verification / Alternative check:

Datasheets from multiple vendors list VO = +14 V typical for 7814, with dropout and line/load regulation specs ensuring stable +14 V when input exceeds VO + dropout.

Why Other Options Are Wrong:

• –14 V dc: negative outputs belong to 79xx series.
• ±8 V options: wrong suffix and wrong polarity for 78xx family.

Common Pitfalls:

• Confusing 7815 (15 V) with 7814 (14 V).
• Ignoring dropout; if input is too low, regulation will be lost.

Final Answer:

+14 V dc