LM317 Adjustable Voltage Regulator TO-92

LM317 Adjustable Voltage Regulator TO-92 is a versatile 3-terminal positive voltage regulator capable of supplying over 100mA of load current across a wide adjustable output range. It is typically used for small regulated power supplies, battery chargers, and low-power applications. Its compact TO-92 package makes it suitable for space-constrained projects.

Key Features:

• Adjustable Output Voltage: Output voltage range from 1.25V to 37V.
• Thermal Overload Protection: Automatically shuts down when temperature exceeds safe limits.
• Current Limiting: Built-in protection against overcurrent damage.
• Low Standby Current: Helps save power in low-load situations.
• Compact TO-92 Package: Ideal for prototyping and small-scale designs.

Technical Specifications:

• Output Voltage Range: 1.25V to 37V
• Maximum Output Current: 100mA to 150mA (TO-92 version)
• Line Regulation: 0.01%/V (typical)
• Load Regulation: 0.1% (typical)
• Dropout Voltage: 1.7V (typical)
• Operating Temperature: 0°C to +125°C

Mechanical Specifications:

• Package Type: TO-92 (Plastic Transistor Case)
• Pin Configuration: Pin 1 (Adjust), Pin 2 (Output), Pin 3 (Input)
• Lead Pitch: 1.27mm
• Body Dimensions: Approx. 4.5mm × 4.0mm × 5.2mm

Mounting Options:

• Through-Hole Mount: Easily inserted into breadboards and PCBs.
• Heatsinking Option: Can be used with small clip-on heatsinks for improved thermal performance.

Schematic Diagram, Connection, Wiring and Pinout:

• Pin 1 (Adjust): Connected to a resistor divider network.
• Pin 2 (Output): Supplies regulated voltage to load.
• Pin 3 (Input): Connect to unregulated DC supply.
• Wiring: Use proper decoupling capacitors for stable operation.

Datasheet and Documentation:

• Download LM317 TO-92 Datasheet (PDF)

Applications:

• Adjustable Power Supplies: Easily build custom regulated supplies.
• Battery Chargers: Controls charging voltage with simple circuitry.
• LED Drivers: Regulate voltage for low-current LED strips.
• Portable Devices: Suitable for compact, low-power designs.
• Embedded Systems: Provides stable voltage for microcontroller circuits.

Equivalent Models:

• LM1117-ADJ: Low-dropout adjustable regulator with similar functionality
• AMS1117-ADJ: Compact regulator with improved thermal profile
• LT3080: Precision adjustable regulator with higher output current

Package Includes:

• 1 x LM317 Adjustable Voltage Regulator TO-92