Key Selection Information
| Selection Parameter | Confirmed Information |
|---|---|
| Regulator Type | Fixed positive LDO |
| Output Voltage | 3.3 V |
| Output Current | Up to 800 mA |
| Maximum Input Voltage | 15 V |
| Typical Dropout | About 1.2 V at 800 mA |
| Package | SOT-223 / DCY, large tape and reel |
Product Overview
LM1117MPX-3.3/NOPB is the fixed 3.3 V large-reel SOT-223 version of TI’s LM1117 linear-regulator family. It is intended for straightforward 3.3 V point-of-load regulation where the source remains sufficiently above the output voltage and the PCB can dissipate the resulting linear-regulator heat.
The practical current limit is strongly thermal. A high VIN-to-VOUT difference converts directly into package dissipation, so the 800 mA electrical rating must be checked together with ambient temperature, copper area and airflow.
Technical Specifications
| Group | Parameter | Value / Condition |
|---|---|---|
| Output | Nominal voltage | 3.3 V |
| Output | Current | Up to 800 mA |
| Input | Maximum voltage | 15 V |
| Regulation | Dropout | About 1.2 V at 800 mA |
| Stability | Output capacitance | 10 µF minimum per TI guidance |
| Protection | Integrated | Current limiting and thermal protection |
| Package | Type | SOT-223 / DCY |
Functional Highlights
Fixed 3.3 V output reduces external parts
The fixed-output orderable code does not require the external feedback divider used by adjustable variants.
Thermal design sets the usable current at high VIN
Power dissipation is approximately (VIN − 3.3 V) × IOUT, so board-level thermal resistance can become the limiting factor before the electrical current limit is reached.
Applications / Application Fit
- 3.3 V point-of-load regulation
- Post-regulation after a switching converter
- BOM-controlled service and replacement builds requiring the exact TI orderable code
Design Considerations
Maintain enough input headroom above 3.3 V across tolerance and load.
Follow TI’s output-capacitor value and ESR requirements for stable operation and transient response.
Verify junction temperature using the actual board copper and ambient conditions.
Related Engineering Resources
- Texas Instruments LM1117 official part page — manufacturer-controlled product information and documentation.
Quality & Verification Support
Third-party inspection or testing can be arranged according to customer requirements. Testing fees are borne by the buyer. Additional verification requirements can be discussed before shipment. After an order is placed, physical product, label, packaging, and Date Code photos may be provided where appropriate.
Request a Quote
To request a quotation, provide the manufacturer part number, required quantity, destination, target Date Code if applicable, and any testing or inspection requirements.
