LM317 – 1.5A, Adjustable Voltage Regulator

The LM317 PDF datasheet can download.

This product has adjustable 3−terminal positive voltage regulator functions.

This is one of the OP amp types. This part name is LM317.

Manufacturers of product is ON semiconductor, other.

The package is TO-220 or D2Pak-3.

Image and pinouts:

LM317 - Voltage Regulator

Some of the text files within the PDF file

The LM317 offers the advantage of adjustable output voltage, making it suitable for a wide range of applications where a specific voltage level is required. It is commonly used in power supplies, battery chargers, voltage references, and other electronic circuits.

The op amp has three pins: input (Vin), output (Vout), and an adjustment pin (ADJ). The input voltage, Vin, is typically higher than the desired output voltage, and the output voltage, Vout, is regulated and adjusted based on the reference voltage and external resistors connected to the ADJ pin.

The device operates by maintaining a constant voltage difference between the ADJ pin and the output pin. The reference voltage between the ADJ pin and the output pin is approximately 1.25V. By selecting appropriate resistor values, the output voltage can be adjusted according to the desired voltage level using the formula provided in the LM317 datasheet.

The LM317 can handle input voltages up to 40V, and it is capable of providing an output current of up to 1.5A, depending on the thermal conditions and the use of appropriate heatsinks. However, the actual output current should be limited based on the power dissipation requirements of the LM317.



• Output Current in Excess of 1.5 A
• Output Adjustable between 1.2 V and 37 V
• Internal Thermal Overload Protection
• Internal Short Circuit Current Limiting Constant with Temperature
• Output Transistor Safe−Area Compensation
• Floating Operation for High Voltage Applications
• Eliminates Stocking many Fixed Voltages
• Available in Surface Mount D2PAK−3, and Standard 3−Lead
Transistor Package
• NCV Prefix for Automotive and Other Applications Requiring
Unique Site and Control Change Requirements; AEC−Q100
Qualified and PPAP Capable
• These Devices are Pb−Free, Halogen Free/BFR Free and are RoHS

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Please refer to the file for details.

LM317 Pinout Datasheet