onsemi LM2576D2T-15G

Overview

LM2576D2T-15G from onsemi is a monolithic 3.0 A, 15 V fixed-output step-down (buck) switching regulator in D2PAK (TO-263) package. It operates from 18–40 V input, delivers ±4% output voltage accuracy over line/load/temperature, features 52 kHz fixed-frequency internal oscillator, cycle-by-cycle current limiting, thermal shutdown, and TTL-compatible ON/OFF control - used in industrial power supplies requiring high efficiency and minimal external components.

For engineers reviewing the LM2576D2T-15G datasheet, pinout, applications, or equivalent options, key selection criteria include guaranteed 3.0 A output current, 15 V fixed output with ±4% tolerance, D2PAK thermal performance (R_JC = 5.0 °C/W), 80 µA standby current in shutdown, and compatibility with standard off-the-shelf 100 µH inductors.

Technical Context

The LM2576D2T-15G integrates a 1.0 A NPN switch, 1.235 V bandgap reference, error amplifier, 52 kHz oscillator, and thermal/current protection circuitry. Its fixed 15 V output eliminates external feedback resistors, simplifying design versus adjustable variants.

It uses voltage-mode PWM control with fixed frequency and variable duty cycle (up to 98%), enabling predictable EMI filtering. The internal 3.1 V regulator powers bias circuitry, while the ON/OFF pin accepts TTL-level logic (V_IL ≤ 1.0 V, V_IH ≥ 2.2 V) for low-quiescent shutdown.

Key Specifications

Pinout & Package

D2PAK (TO-263) package with exposed metal tab thermally and electrically connected to Pin 3 (GND). Heatsink surface must be isolated from other PCB planes except GND.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM2576T-15G, the LM2576D2T-15G offers superior thermal performance in high-power-density layouts; compared with LM2596S-15, it delivers higher efficiency above 24 V input and simpler EMI compliance, at the cost of larger magnetics.

Availability

LM2576D2T-15G is available at Aetrix Electronics and suitable for industrial PLC power supplies, automotive camera modules, and test equipment auxiliary rails requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for LM2576D2T-15G 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power management, analog, and sensing technologies for automotive, industrial, and cloud infrastructure markets.

The LM2576 series was designed as a cost-optimized, easy-to-use buck regulator family targeting industrial and embedded applications where reliability, thermal robustness, and minimal external component count are prioritized over ultra-high frequency or digital control.

FAQ

What is the maximum input voltage for the LM2576D2T-15G?

The LM2576D2T-15G supports a maximum input voltage of 40 V DC, with absolute maximum rating at 45 V. Operation above 40 V risks exceeding safe operating area limits and triggering thermal shutdown. For reliable 15 V output, minimum input is 18 V per datasheet specifications - below this, dropout occurs and regulation is lost. Always include input transient suppression if used in automotive or industrial environments.

Does the LM2576D2T-15G require an external feedback resistor network?

No, the LM2576D2T-15G does not require external feedback resistors. As a fixed-output variant, its 15 V regulation is achieved via an internal resistor divider connected to the Feedback (Pin 4) terminal. This eliminates component count, layout sensitivity, and drift-related inaccuracies common in adjustable configurations - a key advantage for production stability and cost reduction.

What type of catch diode is recommended for the LM2576D2T-15G?

A Schottky diode rated for ≥3.0 A average current and ≥30 V reverse voltage is recommended, such as MBR360 (40 V, 3 A) or SR503 (30 V, 5 A). The diode must handle peak currents up to 7.5 A during current-limit events and exhibit low forward voltage to preserve efficiency. Fast recovery diodes are acceptable but Schottky types minimize conduction losses and switching losses in the 52 kHz topology.

Can the LM2576D2T-15G be used in a negative-output (buck-boost) configuration?

Yes, the LM2576D2T-15G can be configured as a positive-to-negative converter using the standard buck-boost topology shown in the datasheet. In this mode, Pin 2 (Output) becomes the negative output node, and Pin 3 (GND) serves as the return. Output magnitude remains 15 V, but polarity reverses. Layout must maintain strict ground separation and minimize parasitic inductance in the high-di/dt paths.

Is the LM2576D2T-15G still in active production?

Yes, the LM2576D2T-15G remains in active production per onsemi's official product status documentation and distributor inventory (Digi-Key, Mouser). While some older suffixes (e.g., LM2576T-15) have been discontinued, the D2T-15G variant is explicitly listed as active with full datasheet support through April 2025 Rev. 11 - confirming ongoing manufacturing and long-term availability for industrial designs.