The LM317M and LM317MQ are adjustable three-pin, positive-voltage regulators capable of supplying an output current of 0.5A over an output voltage range of 1.25V to 37V. The device requires only two external resistors to set the output voltage. The device features a typical line regulation of 0.01% and typical load regulation of 0.1%. The device includes current limiting, thermal overload protection, and safe operating area protection.
The device is a floating regulator meaning there is no device ground terminal. Quiescent current flows to the load instead of being wasted flowing to ground. Regulated output voltage of hundreds of volts is possible if the maximum input to output differential does not exceed 40V at any time. The device functions as a floating current source controlled by a single resistor.
Additionally, the device does not need an output capacitor for stable operation across the load current range. Optionally, add an electrolytic or tantalum output capacitor to improve transient response. Ceramic output capacitors are available, but output ringing is potentially present on transients. Bypass the ADJUST pin with any type of capacitor to achieve high ripple-rejection ratios.
| Type | Title | Date | ||
|---|---|---|---|---|
| * | Data sheet | LM317M, LM317MQ 3-Pin Adjustable Regulators datasheet (Rev. Q) | PDF | HTML | 25 Jul 2025 |
| Application note | LDO Noise Demystified (Rev. B) | PDF | HTML | 18 Aug 2020 | |
| Application note | LDO PSRR Measurement Simplified (Rev. A) | PDF | HTML | 09 Aug 2017 | |
| Application note | Method For Cal Output Voltage Tolerances in Adj Regs (Rev. A) | 05 May 2013 | ||
| Application note | A New Production Technique for Trimming Voltage Regulators | 03 Oct 2002 | ||
| Application note | Adjustable 3-Terminal Regulator for Low-Cost Battery Charging Systems | 03 Oct 2002 |
For additional terms or required resources, click any title below to view the detail page where available.
The MLTLDO2EVM-037 multipackage low-dropout (LDO) evaluation module (EVM) allows design engineers to evaluate the operation and performance of several common packages of linear regulators for possible use in their own circuit application. This EVM configuration contains a DDA, 3-pin and 5-pin KVU, (...)
| Package | Pins | CAD symbols, footprints & 3D models |
|---|---|---|
| SOT-223 (DCY) | 4 | Ultra Librarian |
| TO-252 (KVU) | 3 | Ultra Librarian |
Recommended products may have parameters, evaluation modules or reference designs related to this TI product.
Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.
If you have questions about quality, packaging or ordering TI products, see TI support.