onsemi LM2596TADJG

Overview

LM2596TADJG from onsemi is a monolithic 3.0 A step-down (buck) switching regulator IC with adjustable output voltage (1.23 V to 37 V), 150 kHz fixed-frequency internal oscillator, and integrated 3.0 A power switch. It features internal loop compensation, thermal shutdown, cycle-by-cycle current limiting, and TTL-compatible ON/OFF control - designed for high-efficiency DC-DC conversion in space-constrained industrial power supplies.

For engineers reviewing the LM2596TADJG datasheet, pinout, applications, or equivalent options, key selection criteria include input voltage range (4.5–40 V), output load capability (3.0 A), feedback reference voltage (1.23 V ±4%), saturation voltage (1.5 V typ), and TO-220-5 package thermal performance (R_θJC = 5.0 °C/W).

Technical Context

The LM2596TADJG implements voltage-mode PWM control with a 1.235 V bandgap reference, fixed 150 kHz oscillator, and error amplifier driving an integrated 3.0 A NPN switch. Its internal compensation eliminates external compensation components, simplifying design while maintaining stability across 1.23–37 V output programming via resistive divider on the Feedback pin.

Protection architecture includes cycle-by-cycle current limit (4.2–7.5 A peak), thermal shutdown at 150 °C, and logic-controlled shutdown with 80 µA standby current. The ON/OFF pin accepts TTL-level signals (V_IL ≤ 1.0 V, V_IH ≥ 2.2 V) to disable regulation and reduce total input current.

Key Specifications

Pinout & Package

LM2596TADJG is supplied in a 5-lead TO-220 package (Case 314D, T suffix), with heatsink surface electrically connected to Pin 3 (GND). The package provides low thermal resistance (R_θJC = 5.0 °C/W) for direct heatsink mounting and robust power dissipation in convection-cooled environments.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM2596TADJG, LM2596S-ADJ offers identical regulation performance in a surface-mount form factor, while MP1584EN-LF-Z trades thermal robustness and pin compatibility for higher-frequency operation and reduced passive size - neither is pin-to-pin replaceable without layout or schematic changes.

Availability

LM2596TADJG is available at Aetrix Electronics and suitable for industrial PLC power supplies, automotive aftermarket converters, point-of-load telecom modules, and battery-powered test equipment requiring stable component supply and long-term manufacturability.

Supply support for LM2596TADJG 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 is a global semiconductor supplier focused on energy-efficient electronics, with leadership in power management, analog, and intelligent power solutions for automotive, industrial, and cloud infrastructure markets.

The LM2596 series was designed as a cost-optimized, easy-to-use buck regulator family targeting medium-current (up to 3 A), medium-voltage (≤40 V) applications where simplicity, reliability, and thermal performance outweigh ultra-high efficiency or ultra-small footprint requirements.

FAQ

What is the maximum input voltage rating for LM2596TADJG?

The absolute maximum supply voltage for LM2596TADJG is 45 V, but the recommended operating range is 4.5 V to 40 V. Exceeding 40 V may trigger internal protection or degrade long-term reliability. The device's 150 kHz switching frequency and internal current limit help maintain safe operation within this range, and LM2596TADJG datasheet Figure 11 confirms stable operation down to 4.5 V input at full load.

How do I calculate the output voltage for LM2596TADJG?

LM2596TADJG output voltage is set by a resistor divider on the Feedback pin using V_OUT = 1.23 V × (1 + R2/R1). R1 is typically 1.0–5.0 kΩ (1% metal film recommended); for 5.0 V output, R1 = 1.0 kΩ and R2 = 3.0 kΩ yields V_OUT = 1.23 × (1 + 3.0/1.0) = 4.92 V. The LM2596TADJG feedback reference has ±4% tolerance, so final output accuracy depends on resistor tolerance and temperature drift.

Does LM2596TADJG require external compensation components?

No, LM2596TADJG features fully internal loop compensation - no external capacitors or resistors are needed for stability. This is confirmed in the datasheet "Features" section and Figure 1 block diagram, where the error amplifier and compensation network are shown as internal. Designers only need to select appropriate output capacitance (e.g., 220 µF low-ESR) and inductance (e.g., 33 µH) per the application circuit in LM2596TADJG Figure 15.

What thermal considerations apply to LM2596TADJG in TO-220 package?

LM2596TADJG in TO-220 (Case 314D) has R_θJC = 5.0 °C/W and R_θJA = 65 °C/W. To maintain T_J ≤ 125 °C at 3.0 A load, a heatsink with ≤15 °C/W thermal resistance is recommended when ambient exceeds 50 °C. The heatsink surface is electrically connected to Pin 3 (GND), so isolation washers are required if mounting to chassis ground.

Can LM2596TADJG be used in negative-output configurations?

Yes - LM2596TADJG can be configured as a negative-output buck-boost converter per datasheet Applications section and Figure 21 (not shown in excerpt but referenced in full document). In this topology, the IC regulates a negative voltage referenced to system ground, with the output capacitor polarity reversed. However, the standard application is positive buck; negative operation requires careful attention to grounding, feedback referencing, and diode placement to avoid latch-up.