Product Description
A highly reliable linear voltage regulator step-down module based on the classic LM317 IC, ideal for providing clean, low-noise adjustable DC power in Arduino, sensor interfacing, and prototyping projects. This versatile buck converter accepts an input voltage up to 40V and steps it down safely to an adjustable output range starting as low as 1.2V. It features a high-precision multi-turn potentiometer that enables incredibly fine voltage adjustments, ensuring your sensitive logic circuits receive the exact power configuration required. Unlike high-frequency switching regulators, this linear module generates zero switching ripple, making it the perfect choice for powering precision analog-to-digital converters, audio pre-amplifiers, and radio-frequency (RF) communication setups.
Pinout / Layout Connections
The power module features clearly labeled terminal input and output solder pads:
VIN+ Pad: Connects to the positive (+) terminal of the unregulated input DC power source (4.5V to 40V).
VIN- / GND Pad: Connects to the common negative (-) reference of the input power supply.
VOUT+ Pad: Outputs the regulated, user-adjusted positive (+) DC voltage (1.2V to 37V).
VOUT- / GND Pad: Connects to the common negative (-) ground return line for your load circuit.
Note: The input voltage must be at least 1.5V to 2.0V higher than the desired output voltage to maintain stable regulation.
Applications
Precision Analog Bench Supplies: Perfect for powering sensitive operational amplifiers, high-resolution ADCs, and delicate sensor nodes requiring ripple-free DC power.
Laboratory Breadboard Prototyping: Excellent as an adjustable secondary power rail for matching non-standard voltage logic chips in embedded designs.
Low-Noise Audio Powering: Ideal for small audio mixers, microphone pre-amp circuits, and DIY headphone amplifiers where switching noise would degrade sound quality.
Compatibility
The LM317 Step-Down Module functions entirely as a hardware-level analog voltage regulator, making it universally compatible with:
Arduino, ESP32, and ESP8266 development boards (Safely steps down 12V or 24V industrial supply lines to clean 5V or 3.3V rails).
Raspberry Pi and single-board computers.
Any DC load device operating within the module’s 1.5A maximum current constraint.
Technical Specifications
| Parameter | Value / Specification |
| Regulator IC Type | LM317 Adjustable Linear Regulator |
| Input Voltage Range | DC 4.5 V to 40 V |
| Output Voltage Range | DC 1.2 V to 37 V (Adjustable via onboard trimmer) |
| Minimum Voltage Differential | 1.5 V to 2.0 V (Input must be greater than output) |
| Output Current Capacity | 1.5 A maximum (Continuous output below 0.5A recommended without external cooling) |
| Regulator Architecture | Linear (Low-noise, zero high-frequency switching ripple) |
| Operating Temperature Range | 0 °C to +125 °C (Thermal shutdown protection built-in) |
What’s in the Box
1 x LM317 DC-DC Step-Down Adjustable Power Regulator Module.




