Texas Instruments LM2595T-3.3

Overview

LM2595T-3.3 from Texas Instruments is a monolithic 150-kHz nonsynchronous step-down DC-DC converter delivering up to 1 A output current with fixed 3.3-V output, ±4% output voltage tolerance over line and load, 4.5–40 V input voltage range, and integrated thermal shutdown and current-limit protection. It serves as a primary buck regulator in industrial power supplies and embedded system rails.

For engineers reviewing the LM2595T-3.3 datasheet, LM2595T-3.3 pinout, LM2595T-3.3 application, or LM2595T-3.3 equivalent, key selection criteria include its fixed 3.3-V output, TO-220-5 package thermal performance, 1-A continuous load capability, and compatibility with standard off-the-shelf inductors and catch diodes in minimal-component buck designs.

Technical Context

The LM2595T-3.3 integrates a PWM controller, power switch, and internal frequency compensation operating at a fixed 150-kHz switching frequency. Its architecture uses external feedback sensing only for adjustable versions; the 3.3-V variant has internal resistor divider, eliminating the need for external feedback components.

It features TTL-compatible ON/OFF control with 1.3-V threshold, 85-μA standby quiescent current, and self-protection via two-stage current limiting and thermal shutdown. The device operates in continuous conduction mode by default but supports discontinuous mode at light loads without loop instability.

Key Specifications

Pinout & Package

LM2595T-3.3 is supplied in a 5-pin TO-220 package (NDH) with tab connected to Pin 3 (Ground), enabling direct heatsink mounting. Package dimensions: 14.986 mm × 10.16 mm × 4.83 mm (L × W × H), lead pitch 2.54 mm.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar step-down regulator applications.

Compared with LM2596T-3.3 and MP1584EN-LF-Z, the LM2595T-3.3 provides optimal balance of proven reliability, TO-220 thermal robustness, minimal external component count, and precise 3.3-V regulation - making it ideal for cost-sensitive, thermally challenging, or long-lifecycle industrial applications where 1-A output suffices.

Availability

LM2595T-3.3 is available at Aetrix Electronics and suitable for industrial PLCs, automotive body control units, FPGA point-of-load supplies, and medical sensor interfaces requiring stable component supply across extended product lifecycles.

Supply support for LM2595T-3.3 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 leader specializing in analog, embedded processing, and power management ICs, with decades of expertise in high-reliability power conversion solutions.

The LM2595 series belongs to TI's SIMPLE SWITCHER® portfolio - designed specifically for ease-of-use, minimal external component count, and robust operation in industrial and automotive power supply applications.

FAQ

What is the maximum input voltage the LM2595T-3.3 can handle?

The LM2595T-3.3 supports an absolute maximum input voltage of 45 V per datasheet Absolute Maximum Ratings, with recommended operation up to 40 V. This allows reliable use in 24-V industrial systems and automotive applications experiencing load dump transients. Exceeding 40 V continuously risks exceeding thermal limits or triggering protection circuits, so design margins should maintain VIN ≤ 40 V under all operating conditions for the LM2595T-3.3.

Does the LM2595T-3.3 require an external feedback resistor network?

No - the LM2595T-3.3 is a fixed-output variant with internal resistor divider set to 3.3 V, so no external feedback resistors are required. This simplifies layout, improves accuracy (±4% over line/load/temperature), and eliminates drift-related errors common in external networks. Only the adjustable LM2595 versions require external resistors; the LM2595T-3.3 delivers its rated output directly from pins 2, 3, and 1 with just input/output capacitors, inductor, and catch diode.

Can the LM2595T-3.3 be used in a negative-output (inverting) configuration?

Yes - the LM2595T-3.3 can be configured as a positive-to-negative inverter by bootstrapping its ground pin to the negative output, as documented in TI's LM2595 datasheet Figure 18. In this topology, it generates −3.3 V from a positive input, with startup hysteresis (ON at ~13 V, OFF at ~8 V). However, output current capability decreases with increasing |VIN| + |VOUT|, and the LM2595T-3.3's 40-V max input rating still applies to the total voltage across its pins.

What thermal performance can be expected from the LM2595T-3.3 in TO-220 package?

In a standard 1-in² PCB copper area, the LM2595T-3.3 achieves RθJA ≈ 50°C/W. At 1-A load and 12-V input, dissipation is ~1.1 W, resulting in ~55°C junction rise above ambient - well within the 125°C max operating junction temperature. No heatsink is required below 50°C ambient; for higher ambient or sustained 1-A loads, attaching the tab (Pin 3) to a heatsink reduces RθJA to ~20°C/W, enabling full-rated operation up to 70°C ambient for the LM2595T-3.3.

Is the LM2595T-3.3 RoHS compliant and halogen-free?

Yes - the LM2595T-3.3 is manufactured by Texas Instruments in RoHS-compliant, lead-free, and halogen-free packaging per TI's official product change notices and packaging specifications. The TO-220-5 NDH package uses matte tin lead finish and meets JEDEC J-STD-020 moisture sensitivity level 3 (MSL-3), ensuring compatibility with standard reflow profiles and environmental compliance requirements for the LM2595T-3.3.