Texas Instruments LM2575T-5.0/LF04

Overview

LM2575T-5.0/LF04 from Texas Instruments is a monolithic 1A step-down (buck) switching voltage regulator in TO-220 package, delivering fixed 5.0V ±4% output with 77% efficiency at 12V input/1A load, 52 kHz fixed-frequency operation, and integrated thermal shutdown/current limiting. It replaces linear regulators in industrial power supplies requiring compact, high-efficiency DC-DC conversion.

For engineers reviewing the LM2575T-5.0/LF04 datasheet, LM2575T-5.0/LF04 pinout, LM2575T-5.0/LF04 application, or LM2575T-5.0/LF04 equivalent, key selection criteria include input voltage range (up to 40V), output accuracy under line/load variation, thermal resistance (65°C/W junction-to-ambient, no heatsink), TTL shutdown capability (50 μA standby), and compatibility with standard off-the-shelf inductors.

Technical Context

The LM2575T-5.0/LF04 integrates a PWM controller, power switch, oscillator, error amplifier, and protection circuitry into a single TO-220 device. Its 52 kHz fixed-frequency architecture enables predictable EMI filtering and simplifies inductor selection using standardized 330 µH parts. The internal 1.23V reference feeds a resistive feedback network that is omitted in fixed-output variants like this one.

Operation relies on cycle-by-cycle current limiting (2.2 A peak), thermal shutdown at 150°C junction temperature, and TTL-compatible ON/OFF control (VIH = 2.2 V min, VIL = 1.0 V max). Dropout behavior is defined by minimum duty cycle (93%) and saturation voltage (0.9 V typ at 1A), enabling stable regulation down to ~7.5V input for 5V output.

Key Specifications

Pinout & Package

LM2575T-5.0/LF04 uses a 5-lead TO-220 package (Package Number NDH0005D) with exposed tab electrically connected to Pin 2 (Output). Mounting requires thermal interface to heatsink or copper pour for >0.5 A continuous loads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM2575T-5.0/LF04, the base LM2575T-5.0 provides identical performance with standard RoHS compliance, while MP1584EN-LF-Z trades input voltage headroom and capacitor flexibility for higher switching frequency and reduced footprint - making LM2575T-5.0/LF04 the preferred choice for industrial reliability and design reuse.

Availability

LM2575T-5.0/LF04 is available at Aetrix Electronics and suitable for industrial power supplies, embedded controller boards, and test equipment requiring stable component supply with long-term manufacturability and extended temperature support.

Supply support for LM2575T-5.0/LF04 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 and embedded processing technologies, with decades of expertise in power management ICs.

The LM2575 series was designed as a drop-in replacement for linear regulators in medium-power DC-DC conversion, targeting cost-sensitive industrial, automotive, and consumer applications needing simplicity and ruggedness.

FAQ

What is the maximum input voltage rating for LM2575T-5.0/LF04?

The absolute maximum input voltage for LM2575T-5.0/LF04 is 45 V, but the recommended operating maximum is 40 V per the datasheet's operating ratings. Exceeding 40 V risks violating the specified output voltage accuracy (±4%) and may trigger thermal shutdown under sustained load. For 60 V input applications, the LM2575HVT-5.0 variant must be used instead.

Does LM2575T-5.0/LF04 require an external feedback resistor network?

No, LM2575T-5.0/LF04 does not require external feedback resistors because it is a fixed-output version with internal resistor divider set to 5.0 V. The Feedback (Pin 4) is pre-connected to the internal 1.23 V reference and output tap - unlike the adjustable LM2575-ADJ variant, which mandates external R1/R2.

Can LM2575T-5.0/LF04 drive a 1 A load continuously without a heatsink?

Yes, LM2575T-5.0/LF04 can deliver 1 A continuously at 25°C ambient with no heatsink when mounted on a PCB with ≥4 in² copper area around the TO-220 tab (θJA = 45°C/W). With minimal copper (θJA = 65°C/W), power dissipation must stay below ~1.5 W - achievable at VIN ≤ 15 V and full load, per thermal calculations in the datasheet.

What type of catch diode is recommended for LM2575T-5.0/LF04?

A Schottky diode rated for ≥1.2 × 1 A = 1.2 A average current and ≥1.25 × VIN(max) = 50 V PIV is recommended. TI specifies the SR103 (3 A, 30 V) or 1N5818 (1 A, 30 V) in typical applications. Fast-recovery diodes like MUR420 are acceptable but less efficient due to higher forward voltage.

Is LM2575T-5.0/LF04 pin-compatible with other LM2575 fixed-output variants?

Yes, all LM2575T-XX fixed-output variants (e.g., LM2575T-3.3, LM2575T-12) share identical TO-220 pinout, electrical interface, and external component requirements - only the internal feedback ratio differs. This allows hardware reuse across voltage options with only output capacitor and inductor value adjustments.