Specifications
| Type | Description |
|---|---|
| Part Number | LM317 |
| Manufacturer | Texas Instruments |
| Product Type | LDO Regulator |
| Category | Power Management |
| Package / Case | TO-220 3-lead Case 221AB; D2PAK-3 Case 936 |
| Component Type | Power_IC |
| Output Current Capability | >1.5 A; General device capability |
| Adjustable Output Voltage Range | 1.2 V to 37 V; General device capability |
| Input-Output Voltage Differential | -0.3 V to 40 V; Maximum rating |
| Power Dissipation | Internally limited; Case 221A, TA=25°C |
| Thermal Resistance Junction-to-Ambient | 65 °C/W; Case 221A |
| Thermal Resistance Junction-to-Case | 5.0 °C/W; Case 221A |
| Power Dissipation | Internally limited; Case 936 D2PAK-3, TA=25°C |
| Thermal Resistance Junction-to-Ambient | 70 °C/W; Case 936 D2PAK-3 |
| Thermal Resistance Junction-to-Case | 5.0 °C/W; Case 936 D2PAK-3 |
| Operating Junction Temperature Range | -55°C to +150°C; Maximum rating |
| Storage Temperature Range | -65°C to +150°C; Maximum rating |
| Line Regulation | typ 0.01 %/V, max 0.04 %/V; TA=25°C, 3.0 V <= VI-VO <= 40 V |
| Load Regulation | typ 5.0 mV, max 25 mV; TA=25°C, 10 mA <= IO <= Imax, VO <= 5.0 V |
| Load Regulation | typ 0.1%, max 0.5% VO; TA=25°C, 10 mA <= IO <= Imax, VO >= 5.0 V |
| Thermal Regulation | typ 0.03 %VO/W, max 0.07 %VO/W; TA=25°C, 20 ms pulse |
| Adjustment Pin Current | typ 50 uA, max 100 uA; VI-VO=5.0 V, IO=0.5 A |
| Adjustment Pin Current Change | typ 0.2 uA, max 5.0 uA; 2.5 V <= VI-VO <= 40 V, 10 mA <= IL <= Imax, PD <= Pmax |
| Reference Voltage | min 1.2 V, typ 1.25 V, max 1.3 V; 3.0 V <= VI-VO <= 40 V, 10 mA <= IO <= Imax, PD <= Pmax |
| Line Regulation | typ 0.02 %/V, max 0.07 %/V; 3.0 V <= VI-VO <= 40 V |
| Load Regulation | typ 20 mV, max 70 mV; 10 mA <= IO <= Imax, VO <= 5.0 V |
| Load Regulation | typ 0.3%, max 1.5% VO; 10 mA <= IO <= Imax, VO >= 5.0 V |
| Temperature Stability | typ 0.7% VO; Tlow <= TJ <= Thigh |
| Minimum Load Current to Maintain Regulation | typ 3.5 mA, max 10 mA; VI-VO=40 V |
| Maximum Output Current | min 1.5 A, typ 2.2 A; VI-VO <= 15 V, PD <= Pmax, T package |
| Maximum Output Current | min 0.15 A, typ 0.4 A; VI-VO=40 V, PD <= Pmax, TA=25°C, T package |
| RMS Noise | typ 0.003% VO; TA=25°C, 10 Hz <= f <= 10 kHz |
| Ripple Rejection | typ 65 dB; VO=10 V, f=120 Hz, without CAdj |
| Ripple Rejection | min 66 dB, typ 80 dB; VO=10 V, f=120 Hz, CAdj=10 uF |
| Thermal Shutdown | typ 180°C; Thermal characteristics not subject to production test |
| Long-Term Stability | typ 0.3%, max 1.0% per 1000 hours; TJ=Thigh, TA=25°C, endpoint measurements |
| Recommended Input Bypass Capacitor | 0.1 uF disc or 1.0 uF tantalum; Recommended to reduce sensitivity to input line impedance |
| Recommended Adjustment Bypass Capacitor | 10 uF; Improves ripple rejection about 15 dB at 120 Hz in a 10 V application |
| Recommended Output Capacitor | 1.0 uF tantalum or 25 uF aluminum electrolytic; Output capacitance for stability/ringing suppression |
| Datasheet Status | request_only |
Product Overview
The LM317 is a Texas Instruments adjustable positive voltage regulator in the Power_Management category. It is specified for output current capability greater than 1.5 A and an adjustable output voltage range of 1.2 V to 37 V, with a maximum-rated input-output voltage differential of -0.3 V to 40 V.
Package options listed in the extracted datasheet facts are TO-220 3-lead Case 221AB and D2PAK-3 Case 936. Both packages have internally limited power dissipation at TA=25°C and 5.0°C/W junction-to-case thermal resistance. Junction-to-ambient thermal resistance is 65°C/W for Case 221A and 70°C/W for Case 936 D2PAK-3.
Electrical specifications include 1.25 V typical reference voltage, 50 uA typical adjustment pin current, 0.003% VO typical RMS noise, and ripple rejection of 65 dB without CAdj or up to 80 dB typical with a 10 uF adjustment bypass capacitor. Recommended external capacitors include input bypass, adjustment bypass, and output capacitance values for input impedance sensitivity, ripple rejection, stability, and ringing suppression.
Key Features
- Adjustable positive voltage regulator topology
- Output voltage adjustable from 1.2 V to 37 V
- Output current capability greater than 1.5 A
- Input-output differential rated from -0.3 V to 40 V
- Reference voltage is 1.25 V typical
- Typical RMS noise is 0.003% of VO
- Ripple rejection reaches 80 dB typical with CAdj
- Thermal shutdown is 180°C typical
- Power dissipation is internally limited
- TO-220 and D2PAK-3 package options
Typical Applications
- Adjustable regulated power supplies
- 1.2 V to 37 V regulator rails
- Greater than 1.5 A output regulation
- 10 V applications with improved ripple rejection
- TO-220 through-hole regulator assemblies
- D2PAK-3 surface-mount regulator assemblies
Procurement Notes
When requesting a quote for LM317, buyers should confirm the manufacturer, package or case, required quantity, target date code, compliance documents, packing method, destination country and expected delivery schedule.
If alternatives are acceptable, buyers should share the approved vendor list, required electrical or optical limits, package constraints and qualification requirements. Any alternative part should be reviewed by the buyer's engineering team before production use.
For power IC and power device sourcing, voltage rating, current rating, power dissipation, package thermal performance, protection features, qualification grade and application conditions should be reviewed before approval.
FAQ
What output voltage range does the LM317 support?
The LM317 is specified as an adjustable positive voltage regulator with an adjustable output voltage range from 1.2 V to 37 V, according to the extracted manufacturer datasheet facts.
What packages are listed for the LM317?
The extracted facts list TO-220 3-lead Case 221AB and D2PAK-3 Case 936 package options. The listed junction-to-case thermal resistance is 5.0°C/W for both package cases.
What capacitors are recommended with the LM317?
The extracted facts recommend a 0.1 uF disc or 1.0 uF tantalum input bypass capacitor, a 10 uF adjustment bypass capacitor, and a 1.0 uF tantalum or 25 uF aluminum electrolytic output capacitor.
Technical Review & Sourcing Note
Prepared by LDeepAI Component Sourcing Team. Reviewed for RFQ, documentation and alternative sourcing use. Last updated: July 26, 2026.
This page is based on manufacturer datasheet information and LDeepAI sourcing review. Specifications should be verified against the official manufacturer datasheet before final procurement or design approval. Final electrical, optical and reliability approval should be confirmed by the buyer's engineering team.