Texas Instruments LM1117DT-2.85/NOPB

Overview

LM1117DT-2.85/NOPB from Texas Instruments is a fixed-output, 2.85 V, 800 mA low-dropout linear regulator in SOT-223 package. It delivers ±1% output voltage accuracy over 0°C to 125°C, maintains regulation with only 1.2 V dropout at full load, and integrates thermal shutdown and current limiting. It serves as a post-regulator for DC–DC converters in embedded power rails requiring stable, low-noise 2.85 V supply.

For engineers reviewing the LM1117DT-2.85/NOPB datasheet, LM1117DT-2.85/NOPB pinout, LM1117DT-2.85/NOPB application, or LM1117DT-2.85/NOPB equivalent, key selection factors include its guaranteed 2.85 V output tolerance, SOT-223 thermal performance (R_θJA = 61.6°C/W), minimum 10 µF tantalum output capacitance requirement, and compatibility with standard linear regulator layout practices for stability and PSRR.

Technical Context

The LM1117DT-2.85/NOPB uses an internal bandgap reference trimmed to ±1% accuracy and a PNP pass transistor architecture enabling low dropout. Its feedback network is fully integrated-no external resistors required-unlike the adjustable LM1117-ADJ variant.

It operates across 0°C to 125°C junction temperature, supports input voltages up to 15 V, and sustains 800 mA output while maintaining ≤0.4% load regulation and ≤0.2% line regulation. Protection includes foldback current limiting and thermal shutdown with automatic recovery.

Key Specifications

Pinout & Package

SOT-223 (4-pin) package with exposed thermal tab (pin 2/TAB connected to VOUT). Pin 1 is ADJ/GND (ground for fixed-output variants), pin 3 is VIN, and pin 2/TAB is VOUT. The thermal tab must be soldered to a PCB copper pour for effective heat dissipation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-dropout linear regulator applications.

Compared with TLV1117-285CDR, LM1117DT-2.85/NOPB offers superior output accuracy (±1% vs. ±2%) but lacks extended temperature support; versus LD1117S285TR, it provides tighter regulation and lower dropout-critical for marginal input conditions-but at higher unit cost.

Availability

LM1117DT-2.85/NOPB is available at Aetrix Electronics and suitable for industrial PLC I/O modules, medical sensor nodes, automotive body control units, test & measurement equipment, and portable instrumentation requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for LM1117DT-2.85/NOPB includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor company headquartered in Dallas, Texas, delivering analog and embedded processing solutions for industrial, automotive, and personal electronics markets.

The LM1117 product line was designed specifically for cost-sensitive, high-reliability linear regulation in space-constrained applications-emphasizing low dropout, integrated protection, and compatibility with standard tantalum output capacitors.

FAQ

What is the maximum input voltage rating for LM1117DT-2.85/NOPB?

The absolute maximum input voltage for LM1117DT-2.85/NOPB is 20 V, but the recommended operating maximum is 15 V per TI's SNOS412N datasheet. Exceeding 15 V risks exceeding thermal limits under load and may degrade long-term reliability. For designs using 12 V or 24 V intermediate rails, ensure sufficient input filtering and consider upstream pre-regulation to keep VIN within 4.05–15 V range for optimal LM1117DT-2.85/NOPB performance.

Does LM1117DT-2.85/NOPB require an external capacitor on the ADJ pin?

No-LM1117DT-2.85/NOPB is a fixed-output variant, so the ADJ pin is internally connected to ground and does not require any external capacitor. Unlike the adjustable LM1117-ADJ, this device has no ADJ functionality; pin 1 serves solely as the ground terminal. Adding capacitance to pin 1 provides no benefit and may introduce instability if improperly implemented.

Can LM1117DT-2.85/NOPB be used with ceramic output capacitors?

Yes, LM1117DT-2.85/NOPB is stable with ceramic output capacitors, provided they meet the minimum 10 µF capacitance and 0.3–22 Ω ESR range specified in the datasheet. Use X7R or X5R dielectrics with adequate DC bias derating; avoid high-K ceramics like Z5U that lose capacitance under bias. A 22 µF, 6.3 V, X7R ceramic with ~1 Ω ESR is a robust choice for improved transient response over tantalum.

What is the thermal resistance (R_θJA) of LM1117DT-2.85/NOPB in SOT-223 package?

The junction-to-ambient thermal resistance (R_θJA) for LM1117DT-2.85/NOPB in SOT-223 package is 61.6°C/W, measured with standard JEDEC 2-layer board conditions. Achieving this value requires proper PCB layout: soldering the thermal tab (pin 2/TAB) to ≥25 mm² of 2-oz copper, using multiple vias to inner ground planes, and minimizing trace length between VIN/VOUT pins and their respective capacitors.

Is LM1117DT-2.85/NOPB RoHS compliant and lead-free?

Yes, LM1117DT-2.85/NOPB is RoHS compliant and lead-free. The "/NOPB" suffix explicitly denotes "No Lead (Pb)-Free" per Texas Instruments' part numbering convention. It meets EU RoHS Directive 2011/65/EU and is compatible with standard Pb-free reflow profiles (peak temperature ≤260°C for 4 seconds).