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3 of 4 articles

Adjustable Voltage Regulator LM317

Adjustable output, design formula Vout = 1.25(1+R2/R1).

Darshan N
Updated: 19 March 2026
5 min read

LM317 Adjustable Regulator

Test your ability to design and analyze LM317-based adjustable voltage regulator circuits.

Question 1 of 3

Q1.An LM317 circuit uses R1 = 240 ohms and R2 = 2.4 kohms. Using Vout = 1.25*(1 + R2/R1), the output voltage is:

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