LM2591HVS-ADJ - 60V 1A 150kHz Buck Regulator, Adj | TI
MPN: LM2591HVS-ADJ ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.42 | $3.42 |
| 10 | $3.08 | $30.80 |
| 100 | $2.74 | $274.00 |
| 500 | $2.45 | $1,225.00 |
| 1,000 | $2.18 | $2,180.00 |
LM2591HVS-ADJ Overview
A buck (step-down) switching regulator is a DC-DC converter topology that uses a power switch, an inductor, a diode, and input/output capacitors to convert a higher DC input voltage into a lower DC output voltage at high efficiency (typically 75-88% for the LM2591HV family). It belongs to the broader hierarchy: buck regulator -> DC-DC switching converter -> power management IC -> semiconductor. Compared with linear regulators, buck converters dissipate far less heat because the pass element switches rather than operating in its linear region.
Key features of the LM2591HVS-ADJ include a fixed 150 kHz internal oscillator that allows use of small inductors and filter capacitors, an adjustable output set by two external resistors, internal current limiting, and thermal shutdown for self-protection. The fixed-frequency architecture simplifies EMI filter design, and the TO-263 tab provides a low thermal resistance path (with proper copper area) suitable for continuous 1A output at moderate input voltages.
The device uses a current-mode control loop with internal compensation, eliminating the need for external loop components. The output switch is a 3A-rated DMOS transistor that handles peak inductor currents during the switch-on phase while the external Schottky diode (or the integrated catch diode in some variants) provides the freewheeling path during switch-off.
Typical applications include 48V telecom point-of-load conversion, industrial 24V/36V sensor and actuator supplies, battery charging systems for lead-acid or Li-ion stacks, automotive accessory rails (with input transient protection), and hobby/maker buck modules. The adjustable output and wide VIN range also suit solar charge controllers and distributed DC bus architectures.
When designing with this part, place the input capacitor (≥470 µF low-ESR aluminum or 220 µF ceramic) directly across the input pins with short traces, and minimize the loop area formed by the switch node, diode, and inductor to reduce ringing and EMI. The ON/OFF pin (high = shutdown on some variants, low on others) should be tied to ground (or VOUT per the datasheet) if unused, with a soft-start capacitor if controlled turn-on is required.
This page synthesizes distributor pricing, drop-in pin-compatible alternatives, and practical design notes not found in the standalone manufacturer datasheet.
Drop-in alternatives for LM2591HVS-ADJ — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
LM2591HVS-ADJ/NOPB
✅ Drop-In📋 Reference alternative (not in catalog)
LM2591HVS-ADJ/TR
✅ Drop-In📋 Reference alternative (not in catalog)
LM2591HVSX-ADJ/NOPB
✅ Drop-In📋 Reference alternative (not in catalog)
LM2591HVS-5.0/NOPB
✅ Drop-In📋 Reference alternative (not in catalog)
LM2591HVS-3.3/NOPB
✅ Drop-In📋 Reference alternative (not in catalog)
LM2591HVS-ADJ Maximum Ratings & Electrical Characteristics
| Topology | Buck (Step-Down) Switching Regulator |
| Input Voltage Range (HV) | 4.5 V to 60 V |
| Output Voltage Range | 1.2 V to 57 V (Adjustable) |
| Maximum Output Current | 1 A |
| Switching Frequency | 150 kHz (typ) |
| Switch Current Limit (Internal) | ≈ 3 A peak |
| Feedback Voltage | 1.23 V (typ, ADJ version) |
| Output Voltage Tolerance | ±4% (over line/load) |
| Quiescent Current (Shutdown) | ≈ 90 µA standby |
| Operating Junction Temperature | -40 °C to +125 °C |
| Package | TO-263-5 (KTT) DDPAK, 5 leads + tab |
| Mounting Type | Surface Mount (D2PAK) |
| Efficiency (typ at full load) | 75 % to 88 % (application dependent) |
| Thermal Resistance θJA (TO-263, 2.5 in² Cu) | ≈ 50 °C/W |
| MSL Level | 3 (168 hours) |
| RoHS Status | Compliant (NOPB suffix indicates Pb-free) |
| Protection Features | Current limit, thermal shutdown |
LM2591HVS-ADJ Pin Configuration
| Pin 1 | VIN — Input supply voltage (4.5 V to 60 V) |
| Pin 2 | OUTPUT — Switch node - connects to inductor and freewheel diode |
| Pin 3 | GROUND — Ground reference for the regulator |
| Pin 4 | FEEDBACK — Feedback voltage input (1.23 V reference) |
| Pin 5 | ON/OFF — Shutdown control (tie to GND for enable) |
Typical Applications
LM2591HVS-ADJ is suitable for 6 applications: 48V Telecom Point-of-Load Conversion, Industrial 24V/36V Sensor and Actuator Power, Battery Charging and DC Bus Regulation, Automotive Accessory Rail (Non-Safety), Hobby and Maker DC-DC Buck Modules, Distributed Solar Charge Controllers.
48V Telecom Point-of-Load Conversion
The LM2591HVS-ADJ's 60V input rating makes it ideal for stepping 48V telecom battery rails down to 5V or 3.3V logic rails. Its 150kHz fixed-frequency operation allows use of small inductors while the 1A output supports typical access-network subscriber line cards. Compared with linear regulators, the buck topology dissipates far less power (typically 75-85% efficiency at full load), so it eliminates the need for bulky heatsinks even when dropping 48V to 5V at 1A. The internal current limit and thermal shutdown provide fault protection for hot-plug events common in telecom shelves.
Recommended
Industrial 24V/36V Sensor and Actuator Power
On factory 24V and 36V industrial busses, the LM2591HVS-ADJ provides a compact local point-of-load converter to step the bus down to 12V, 5V, or 3.3V for sensors, motor drivers, and PLC I/O. The wide 4.5V-60V input range tolerates the inductive transients common when switching solenoids and motor loads per IEC 61131-2. The 150kHz switching frequency keeps the converter above the AM broadcast band, simplifying EMI compliance for industrial control cabinets, while the TO-263 tab solders to chassis copper for additional thermal relief.
Recommended
Battery Charging and DC Bus Regulation
The LM2591HVS-ADJ is well-suited for charging 24V lead-acid battery stacks from a higher-voltage solar array or DC bus, thanks to its 60V input rating and adjustable output down to 1.2V. By selecting the feedback resistor divider, designers can program the float voltage precisely (e.g., 27.6V for a 24V battery). The fixed 150kHz switching and predictable inductor ripple current simplify filter design for noisy DC bus environments, while the 90µA standby current minimizes battery drain when charging is disabled via the ON/OFF pin.
Recommended
Automotive Accessory Rail (Non-Safety)
Although the LM2591HVS-ADJ is not AEC-Q100 qualified, it can still serve in non-safety automotive accessories like interior lighting controllers, audio amplifiers, and infotainment accessories where 24V truck or 12V passenger-car rails are common. The 60V input withstands 24V truck jump-start transients (per ISO 7637-2) and load-dump events when paired with an external TVS clamp. Designers should add a series fuse and input EMI filter per CISPR 25 Class 5 if the converter feeds noise-sensitive audio paths, and validate thermal performance in the sealed vehicle environment.
Recommended
Hobby and Maker DC-DC Buck Modules
The LM2591HVS-ADJ is the heart of countless commercial buck converter modules sold to hobbyists and makers for stepping 12V/24V/36V down to 5V or 3.3V. Its ease of use (only inductor, diode, capacitors, and two resistors needed) and 1A output suits powering Arduino-class boards, LED strips, and RC battery chargers. The TO-263 package can be soldered to a 1 oz copper pour on a small breakout board, and the 150kHz frequency keeps the module below the audible range, eliminating inductor whine in hobby enclosures.
Recommended
Distributed Solar Charge Controllers
In small off-grid solar systems, the LM2591HVS-ADJ can step a 24V or 36V panel down to charge a 12V battery with adjustable float voltage set by the feedback divider. The 60V input rating tolerates open-circuit panel voltage on cold days (Voc rises as temperature drops per the panel spec sheet). Pair the regulator with a Schottky diode on the input to prevent reverse current at night, and add an MPPT controller upstream if maximum energy harvest is required; the LM2591HVS-ADJ alone provides a simple, low-cost PWM-style alternative.
Recommended
Recommended Products Summary
Engineering reference data for LM2591HVS-ADJ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LM2591HVS-ADJ/NOPB | LM2591HVS-ADJ/TR | LM2591HVSX-ADJ/NOPB | LM2591HVS-5.0/NOPB | LM2591HVS-3.3/NOPB |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | HGSEMI | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | TO-263-5 (KTT) | TO-263-5 (KTT) - same | TO-263-5 (KTT) - same | TO-263-5 (KTT) - same | TO-263-5 (KTT) - same | TO-263-5 (KTT) - same |
| Input Voltage Range | 4.5 V to 60 V | 4.5 V to 60 V | 4.5 V to 60 V | 4.5 V to 60 V | 4.5 V to 60 V | 4.5 V to 60 V |
| Output Voltage | 1.2 V to 57 V (Adj) | 1.2 V to 57 V (Adj) | 1.2 V to 57 V (Adj) | 1.2 V to 57 V (Adj) | 5 V (Fixed) | 3.3 V (Fixed) |
| Maximum Output Current | 1 A | 1 A | 1 A | 1 A | 1 A | 1 A |
| Switching Frequency | 150 kHz | 150 kHz | 150 kHz | 150 kHz | 150 kHz | 150 kHz |
| RoHS Compliance | Check part marking | Yes (Pb-free) | Yes (Pb-free) | Yes (Pb-free) | Yes (Pb-free) | Yes (Pb-free) |
| Operating Temperature Range | -40 °C to +125 °C | -40 °C to +125 °C | -40 °C to +125 °C | -40 °C to +125 °C | -40 °C to +125 °C | -40 °C to +125 °C |
Key Differentiators
- 60V maximum input vs 40V on standard LM2591 (vs LM2591 (non-HV) family)
- 150 kHz switching frequency vs 52 kHz on LM2576 (vs LM2576HVS-ADJ)
- ON/OFF pin for low-power shutdown (vs LM2590HV (no shutdown pin))
- TO-263-5 surface-mount package vs TO-220 through-hole (vs LM2591HV (NDH TO-220 package))
Design Notes
Place the input capacitor (≥220 µF low-ESR type) as close as possible to the VIN and GND pins of the LM2591HVS-ADJ with short, wide traces to minimize input voltage ripple and provide the high di/dt currents demanded by the switching regulator. The catch diode should be a Schottky (e.g., 1N5822 or SS34) with short leads connected to OUTPUT and GND, and the inductor should be rated for at least 3 A peak current with low DC resistance (under 50 mΩ) to maintain efficiency above 80%.
At VIN = 24 V, VOUT = 5 V, and IOUT = 1 A, the LM2591HVS-ADJ dissipates approximately (24-5) × 1 / efficiency, where efficiency is around 80%. Estimated: power dissipation is approximately (24-5) × 1 × (1-0.80)/0.80 ≈ 4.75 W. With TO-263 θJA of about 50 °C/W on 2.5 in² of 1 oz copper (note 13 in the datasheet), the junction rises about 237 °C above ambient, exceeding the 125 °C maximum. Use a larger copper pour, multi-layer PCB inner copper, or an external heatsink for this duty cycle.
Do not exceed the 60 V absolute maximum VIN rating. Add a TVS clamp (e.g., SMBJ58A) on the input if transients above 60 V are possible. The ON/OFF pin polarity differs between some LM2591 variants - confirm on the datasheet before tying it permanently. Always use a Schottky (not standard rectifier) as the catch diode to avoid switching losses that exceed the regulator's dissipation budget and cause thermal shutdown.
Minimize the loop area of the high-current path: VIN → internal switch → OUTPUT pin → inductor → freewheel diode → GND → back to VIN capacitor. Use a ground plane on the bottom layer stitched with vias near the GND pin. Keep the feedback trace away from the switch node and inductor to avoid noise injection that would appear as output ripple. A 10 kΩ / 1 nΩ RC snubber across the Schottky diode can reduce ringing on the switch node in some layouts.
Compliance Information
LM2591HVS-ADJ (without /NOPB) is the legacy tin-lead version; for RoHS compliance specify LM2591HVS-ADJ/NOPB. AEC-Q100 status is not_qualified - this part is for industrial/commercial use, not automotive safety-critical applications. Verify all compliance attributes against the manufacturer's latest material declaration.
