Texas Instruments LM2597HVN-3.3

Overview

LM2597HVN-3.3 from Texas Instruments is a monolithic 150 kHz step-down (buck) switching voltage regulator IC delivering a fixed 3.3 V output at up to 0.5 A, with input voltage support up to 60 V (HV version), ±4% output voltage tolerance over line/load/temperature, and integrated soft-start/shutdown control. It serves as a primary DC-DC power conversion stage in industrial power supplies and embedded systems requiring high-efficiency regulation from wide-input sources.

For engineers reviewing the LM2597HVN-3.3 datasheet, LM2597HVN-3.3 pinout, LM2597HVN-3.3 application, or LM2597HVN-3.3 equivalent, key selection criteria include its 60 V max input rating, 3.3 V fixed output accuracy, thermal shutdown protection, bias supply (VBS) pin for improved high-VIN efficiency, and compatibility with standard off-the-shelf inductors and Schottky catch diodes.

Technical Context

The LM2597HVN-3.3 integrates a 0.5 A N-channel MOSFET switch, 150 kHz fixed-frequency oscillator, internal frequency compensation, and feedback error amplifier. Its architecture uses pulse-width modulation (PWM) in continuous conduction mode, with a two-stage current limit and thermal shutdown for fault protection.

It features a dedicated Bias Supply (VBS) pin that powers internal circuitry independently of VIN, reducing quiescent current and improving efficiency at high input voltages. The device also includes an out-of-regulation error flag with programmable delay and a shutdown/soft-start pin with 1.3 V threshold and sub-10 μA standby current.

Key Specifications

Pinout & Package

The LM2597HVN-3.3 is housed in an 8-pin SOIC (D) surface-mount package (Package Number D0008A), with exposed pad for thermal enhancement. Pin functions are validated per TI SNVS119C Figure 3.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar buck regulator applications.

Compared with LM2597MX-3.3, the LM2597HVN-3.3 provides 20 V higher input voltage margin and better thermal performance in SOIC; versus LM2678-3.3, it trades output current for integrated fault signaling and high-VIN efficiency via VBS-making it optimal for space-constrained, supervisory-critical 0.5 A designs.

Availability

LM2597HVN-3.3 is available at Aetrix Electronics and suitable for industrial automation, automotive electronics, and medical portable equipment requiring stable component supply with long-term manufacturability and consistent parametric performance.

Supply support for LM2597HVN-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 technologies, with decades of expertise in switching regulator design and manufacturing.

The LM2597HVN-3.3 belongs to TI's SIMPLE SWITCHER® family-engineered for ease of use in cost-sensitive, space-constrained DC-DC applications where reliability, minimal external components, and wide input voltage range are critical.

FAQ

What is the maximum input voltage rating for the LM2597HVN-3.3?

The LM2597HVN-3.3 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 LM2597 (40 V max) and enables direct regulation from 48 V industrial buses or automotive battery systems with transient headroom. Operation above 40 V requires the HV variant; using LM2597MX-3.3 in such conditions risks permanent damage.

Does the LM2597HVN-3.3 require external feedback resistors to set its output voltage?

No, the LM2597HVN-3.3 does not require external feedback resistors. It is a fixed-output version with the 3.3 V reference internally trimmed and connected to the FB pin. The FB pin is not user-accessible in this variant and must remain unconnected (no pull-up/down). External resistors are only required for the adjustable LM2597HVN-ADJ variant, where VOUT is set via R1/R2 divider from FB to GND.

How does the VBS pin improve efficiency in the LM2597HVN-3.3?

The VBS pin on the LM2597HVN-3.3 supplies dedicated bias power to internal circuitry-including the gate driver-decoupling it from the main VIN rail. At high input voltages (e.g., 48 V), this reduces power dissipation in the internal LDO and lowers gate drive losses, resulting in higher overall efficiency and lower thermal stress. TI specifies typical operating quiescent current drops from ~5 mA (VIN-only bias) to ~1–2 mA when VBS is properly configured.

What protection features are built into the LM2597HVN-3.3?

The LM2597HVN-3.3 integrates thermal shutdown (150 °C junction cutoff), two-stage current limiting (peak 0.58–1.4 A depending on condition), and an out-of-regulation error flag with programmable delay. It also supports external shutdown via the SD/SS pin (≤0.6 V disables regulator, drawing only 140 μA). These features collectively protect against overcurrent, overtemperature, input dropout, and short-circuit faults without requiring external supervision circuitry.

Can the LM2597HVN-3.3 be used in discontinuous conduction mode (DCM)?

Yes, the LM2597HVN-3.3 operates in both continuous conduction mode (CCM) and discontinuous conduction mode (DCM), automatically transitioning based on load current and inductor value. DCM occurs at light loads (e.g., <100 mA with 100 μH inductor), where the inductor current falls to zero each cycle. TI's datasheet includes waveforms (Figures 22–23) and load transient responses (Figures 24–25) confirming stable DCM behavior, making LM2597HVN-3.3 suitable for variable-load applications like sensor nodes with sleep/wake cycles.