LM317-Voltage Regulator 1.25V to 37V REG21 , R33

DescriptionWhen you graduate from using standard 5V development boards to designing custom embedded systems with modules like the ESP32, SIM7080G, or Air780E, you quickly realize that different components require highly specific operating voltages. The LM317 Adjustable Voltage Regulator is the industry-standard solution for generating exact, stable voltage rails.Whether you are designing a variable bench power supply for a final-year engineering project or stocking up on components for a summer electronics training program, the LM317 provides robust, reliable power management in a standard TO-220 package.The “Two-Resistor” MagicUnlike fixed regulators (which have Ground, Input, and Output pins), the LM317 features an Adjust (ADJ) pin. By wiring a simple voltage divider using two resistors between the Output, Adjust, and Ground pins, you program the exact voltage the chip will output. If you replace one of those fixed resistors with a potentiometer, you instantly have a variable power supply that you can adjust on the fly with the twist of a knob!Built-In IndestructibilityThe LM317 is famous for being incredibly difficult to destroy. It features built-in internal current limiting and thermal shutdown. If your load draws too much current, or if you accidentally short-circuit the output on your breadboard, the chip will automatically throttle itself down or shut off entirely before it melts, making it exceptionally safe for educational environments.Key Features:Fully Adjustable: Set your output voltage anywhere from 1.25V to 37V.High Current Delivery: Can source up to 1.5A of continuous current (provided the TO-220 tab is properly heatsinked).High Ripple Rejection: Provides incredibly clean, stable DC power, perfect for noise-sensitive audio and RF circuits.Thermal Protection: Automatically shuts down if operating temperatures exceed safe limits.Technical Specifications:Regulator Type: Linear (Adjustable)Output Voltage Range: 1.25V to 37V DCMaximum Output Current: 1.5AMaximum Input-to-Output Voltage Differential: 40VLine Regulation: 0.01% / V (Typical)Load Regulation: 0.1% (Typical)Package Type: TO-220 (Through-hole with metal mounting tab)Ideal Applications:Custom adjustable bench power suppliesGenerating specific logic-level voltages (e.g., 3.3V, 1.8V) for microcontrollers and sensorsConstant-current LED drivers and battery charging circuitsPowering 3.8V or 4V cellular and IoT communication modulesCore curriculum hardware for electronics bootcamps and DIY kitsUsage Tip: Because the LM317 is a linear regulator, any excess voltage it drops is converted directly into heat. If you are dropping a 12V input down to 3.3V while drawing 1 Amp, the chip will get extremely hot. Always attach a suitable aluminum heatsink to the TO-220 metal tab for high-current applications.CircuitDocumentDatasheetPackage includes: 1×LM317 Voltage Regulator