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100 mA adjustable linear regulator

LM317L Working Principle

Learn how LM317L works with an illustrated explanation and practical readings.

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LM317L at a glance

Follow the labeled connections and functional stages

LM317L working principle: illustrated functional stages, basic circuit and connections
Select the diagram to read it at full resolution.

How it works

3 stages · Explore one step at a time

Step 1 / 3

Identify the package

TO-92 front-view order is ADJ3, OUT2, IN1. On SOIC, connect all four output contacts.

Step 2 / 3

Set the divider

220 Ω runs from OUT to ADJ and 660 Ω from ADJ to ground. A 500 Ω load draws nominally 10 mA.

Step 3 / 3

Check chip and heat

Read the source chip-origin conditions. A 9-to-5 V example dissipates about 63 mW in the pass stage before small corrections.

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