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.
Products with similar specifications, sorted by available TI.com inventory.
| 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 |
For additional terms or required resources, click any title below to view the detail page where available.
The LM317A-337N-EVM demonstrates canonical application of the LM317A adjustable regulator and its negative complement, the LM337-N. The evaluation module (EVM) is assesmbled with the SOT-223 package option for each device, supplying up to 1 A of load current. The EVM is designed for easy (...)
| Package | Pins | CAD symbols, footprints & 3D models |
|---|---|---|
| SOT-223 (DCY) | 4 | Ultra Librarian |
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