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National Semiconductor LM117/LM317A/LM317 3-Terminal Adjustable Regulator Datasheet
The LM117 series of adjustable 3-terminal positive voltage regulators is capable of supplying in excess of 1.5A over a 1.2V to 37V output range. They are exceptionally easy to use and require only two external resistors to set the output voltage, offering better line and load regulation than standard fixed regulators.
Read onlineNational Semiconductor LM117/LM317A/LM317 specifications
| Output Current (LM117, LM317) | 1.5A |
|---|---|
| Output Voltage Range | 1.2V to 37V |
| Line Regulation (LM317A) | 0.01%/V Typ |
| Ripple Rejection Ratio | 80 dB |
Source: National Semiconductor LM117/LM317A/LM317 3-Terminal Adjustable Regulator Datasheet
All National Semiconductor LM117/LM317A/LM317 documents by type
Ratings, dimensions and ordering codes, for selection and design work.
- National Semiconductor LM117/LM317A/LM317 3-Terminal Adjustable Regulator Datasheet 26 p
- National Semiconductor LM117/LM317A/LM317 Adjustable Regulator Datasheet 28 p
- National Semiconductor LM117/LM317A/LM317 Adjustable Regulator Datasheet 28 p
- National Semiconductor LM117/LM317A/LM317 3-Terminal Adjustable Regulator Data Sheet 26 p
- National Semiconductor LM117/LM317A/LM317 3-Terminal Adjustable Regulator Datasheet 25 p
- National Semiconductor LM117/LM317A/LM317 3-Terminal Adjustable Regulator Datasheet 26 p
- National Semiconductor LM117/LM317A/LM317 3-Terminal Adjustable Regulator Datasheet 25 p
- National Semiconductor LM117/LM317A/LM317 3-Terminal Adjustable Regulator Datasheet 25 p
- National Semiconductor LM117/LM317A/LM317 Datasheet 28 p
- National Semiconductor LM117/LM317A/LM317 Adjustable Regulator Datasheet 26 p
Questions answered in these manuals
How many external resistors are needed to set the output voltage?
The device requires only two external resistors to set the output voltage.
From: National Semiconductor LM117/LM317A/LM317 3-Terminal Adjustable Regulator Datasheet
What is the guaranteed output voltage tolerance for the LM317A?
The guaranteed output voltage tolerance is 1%.
From: National Semiconductor LM117/LM317A/LM317 3-Terminal Adjustable Regulator Datasheet
What input bypass capacitor is recommended for the LM117?
A 0.1 µF disc or 1 µF solid‑tantalum capacitor on the input is suitable for most applications.
From: National Semiconductor LM117/LM317A/LM317 Adjustable Regulator Datasheet
When is a heatsink required for the LM317 series?
A heatsink may be needed if the calculated thermal resistance exceeds the package rating, based on power dissipation and ambient temperature.
From: National Semiconductor LM117/LM317A/LM317 Adjustable Regulator Datasheet
How much ripple rejection can be achieved with the LM117?
The LM117 can achieve up to 80 dB ripple rejection when a 10 µF bypass capacitor is used on the adjustment terminal.
From: National Semiconductor LM117/LM317A/LM317 Adjustable Regulator Datasheet
What are the line‑regulation specifications for the LM317A?
The LM317A provides a line regulation of 0.01 % per volt.
From: National Semiconductor LM117/LM317A/LM317 Adjustable Regulator Datasheet