Texas Instruments LM2597HVMX-12

Overview

LM2597HVMX-12 from Texas Instruments is a monolithic 150 kHz step-down (buck) switching voltage regulator IC delivering a fixed 12 V output at up to 0.5 A, with input voltage support up to 60 V, ±4% output voltage tolerance over line and load, and integrated soft-start/shutdown control. It serves as a primary DC-DC conversion stage in industrial power supplies and battery-powered systems requiring high-input-voltage regulation.

For engineers reviewing the LM2597HVMX-12 datasheet, LM2597HVMX-12 pinout, LM2597HVMX-12 application, or LM2597HVMX-12 equivalent, key selection considerations include its 60 V max input rating, 12 V fixed output, 150 kHz oscillator, thermal shutdown protection, and compatibility with standard off-the-shelf inductors - all critical for ruggedized buck converter design.

Technical Context

The LM2597HVMX-12 implements a current-mode controlled buck topology with an internal 0.5 A N-channel DMOS switch and fixed-frequency 150 kHz oscillator. Its control loop integrates frequency compensation, enabling stable operation with minimal external components.

It features a dedicated bias supply pin (VBS) that powers internal circuitry independently of VIN, improving efficiency at high input voltages, and includes an out-of-regulation error flag with programmable delay via an external capacitor on the DELAY pin.

Key Specifications

Pinout & Package

LM2597HVMX-12 is housed in an 8-pin SOIC (D) surface-mount package (Package Number D0008A), with exposed pad for thermal enhancement. Pin assignments are validated per TI SNVS119C Figure 3.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM2597MX-12, the LM2597HVMX-12 adds 20 V input headroom critical for surge-prone environments; versus LM2596HV-12, it trades current capacity for smaller footprint and integrated flag delay - making it optimal for compact 0.5 A designs needing fault reporting.

Availability

LM2597HVMX-12 is available at Aetrix Electronics and suitable for industrial automation, automotive subsystems, and telecom power conversion requiring stable component supply, long-term lifecycle support, and guaranteed traceability.

Supply support for LM2597HVMX-12 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 technologies, with decades of expertise in switching regulator design.

The LM2597HV product line was engineered for high-input-voltage DC-DC conversion in harsh environments - targeting applications where reliability, simplicity, and wide VIN range outweigh the need for ultra-high efficiency or digital control.

FAQ

What is the maximum input voltage rating for the LM2597HVMX-12?

The LM2597HVMX-12 supports a maximum input voltage of 60 V, as specified in the Absolute Maximum Ratings table of the TI SNVS119C datasheet. This HV rating distinguishes it from the standard LM2597MX-12 (40 V max), enabling use in 48 V systems subject to load-dump transients. Operation above 60 V risks permanent damage.

Does the LM2597HVMX-12 require external feedback resistors to set the 12 V output?

No, the LM2597HVMX-12 is a fixed-output variant - its 12 V regulation is achieved via internal resistor divider, so the FB pin is not connected externally. Unlike the adjustable LM2597HV-ADJ, this part eliminates feedback resistor selection, placement, and tolerance errors, simplifying design and improving output accuracy stability.

How does the VBS pin improve efficiency in the LM2597HVMX-12?

The VBS pin on the LM2597HVMX-12 supplies bias power to internal circuitry independently of VIN. At high input voltages (e.g., >24 V), routing bias from VIN through VBS reduces internal LDO losses, improving overall efficiency by ~3–5% compared to regulators without this feature - particularly beneficial in 36–60 V industrial and telecom applications.

Can the LM2597HVMX-12 be used in a positive-to-negative buck-boost configuration?

Yes - the LM2597HVMX-12 can serve as the core switcher in a positive-to-negative inverting buck-boost converter when paired with appropriate external components (inductor, diode, capacitor). TI Application Note SLVA017 details this topology. The 12 V fixed output version sets the magnitude; polarity inversion occurs via circuit configuration, not IC modification.

What thermal derating applies to the LM2597HVMX-12 in SOIC-8 package?

The LM2597HVMX-12 in SOIC-8 (D package) has a junction-to-ambient thermal resistance (θJA) of 150°C/W with standard PCB copper. At 0.5 A output and 25 V input, typical power dissipation is ~0.55 W - resulting in ~83°C junction rise above ambient. Derating begins above 125°C junction; maintaining <70°C ambient or adding 1 in² copper pour reduces θJA significantly per TI thermal guidelines.