Texas Instruments LM2671MX-5.0/NOPB

Overview

LM2671MX-5.0/NOPB from Texas Instruments is a monolithic step-down (buck) DC-DC switching regulator delivering 5 V at up to 500 mA output current, with ±1.5% output voltage tolerance over line and load, 260 kHz fixed-frequency operation, and integrated 0.25 Ω DMOS power switch. It operates from 6.5 V to 40 V input and targets industrial power rails, embedded system point-of-load conversion, and efficient preregulation for linear regulators.

For engineers reviewing the LM2671MX-5.0/NOPB datasheet, LM2671MX-5.0/NOPB pinout, LM2671MX-5.0/NOPB application, or LM2671MX-5.0/NOPB equivalent, key selection considerations include its fixed 5 V output, SOIC-8 package thermal performance (R_θJA = 105 °C/W), soft-start control via external capacitor, TTL-compatible ON/OFF enable, and synchronization capability for EMI-sensitive designs.

Technical Context

The LM2671MX-5.0/NOPB implements a voltage-mode PWM controller with internal 260 kHz oscillator, fixed-frequency operation enabling predictable EMI filtering, and cycle-by-cycle current limiting with thermal shutdown protection. Its integrated high-side DMOS FET features 0.25 Ω typical R_DS(ON), supporting >90% efficiency at 12 V_IN/5 V_OUT/500 mA.

Functional modes include active regulation (ON/OFF ≥ 1.4 V) and low-power shutdown (ON/OFF ≤ 0.8 V, I_STBY = 50 μA typ). The FB pin is internally connected to the 5 V output divider, eliminating external resistors; soft-start is controlled by an external capacitor on SS, and SYNC allows external clock injection above 275 kHz for frequency coordination.

Key Specifications

Pinout & Package

LM2671MX-5.0/NOPB is packaged in an 8-pin SOIC (D package), 4.90 mm × 3.91 mm body size, with exposed pad not present. Thermal resistance is R_θJA = 105 °C/W under standard JEDEC 2s2p layout.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM2672MX-5.0/NOPB, the LM2671MX-5.0/NOPB offers identical functionality at lower cost for standard industrial temperatures; versus TPS54202DR, it trades higher current and frequency for simplicity, fixed output, and SOIC-8 footprint - making it ideal for cost-sensitive, space-constrained legacy or new designs requiring minimal external components.

Availability

LM2671MX-5.0/NOPB is available at Aetrix Electronics and suitable for industrial automation, embedded computing, and test equipment requiring stable component supply, long-lifecycle support, and SOIC-8 manufacturability.

Supply support for LM2671MX-5.0/NOPB 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 high-reliability power conversion ICs.

The LM2671 series belongs to TI's SIMPLE SWITCHER® family - designed specifically for ease-of-use, minimal external component count, and robust performance in industrial and commercial DC-DC conversion applications.

FAQ

What is the maximum input voltage rating for the LM2671MX-5.0/NOPB?

The LM2671MX-5.0/NOPB has an absolute maximum input voltage rating of 45 V, with recommended operating range from 6.5 V to 40 V. Operation within the recommended range ensures specified performance including ±1.5% output tolerance, 500 mA load capability, and thermal stability. Exceeding 40 V may trigger internal protection but is not guaranteed for continuous operation.

Does the LM2671MX-5.0/NOPB require external feedback resistors to set the 5 V output?

No, the LM2671MX-5.0/NOPB does not require external feedback resistors. It integrates precision internal resistors to set the 5 V output; the FB pin is internally connected to the divider midpoint. This eliminates resistor tolerance errors and layout sensitivity, directly contributing to the ±1.5% output voltage accuracy over temperature and load.

Can the LM2671MX-5.0/NOPB synchronize to an external clock signal?

Yes, the LM2671MX-5.0/NOPB supports external clock synchronization via the SYNC pin. An external TTL/CMOS-compatible signal >275 kHz can be ac-coupled to SYNC to force the switching frequency - useful for EMI reduction and multi-rail timing alignment. Note that current-limit frequency foldback is disabled during sync operation, so short-circuit protection relies solely on cycle-by-cycle current limiting.

What thermal considerations apply to the LM2671MX-5.0/NOPB in SOIC-8 package?

The LM2671MX-5.0/NOPB in SOIC-8 (D package) has a junction-to-ambient thermal resistance (R_θJA) of 105 °C/W under JEDEC-standard 2s2p board conditions. At 500 mA output and 12 V input, dissipation is ~350 mW; this results in ~37 °C rise above ambient - well within the 125 °C max junction limit. No heatsink is required; however, maximizing copper area on GND and VIN traces improves thermal performance.

Is the LM2671MX-5.0/NOPB RoHS-compliant and lead-free?

Yes, the LM2671MX-5.0/NOPB is RoHS-compliant and lead-free. The "/NOPB" suffix explicitly denotes lead-free packaging per JEDEC J-STD-609. It meets EU RoHS Directive 2011/65/EU and TI's green chemistry standards, with no exemptions applied. Full compliance documentation, including material declarations and test reports, is available through TI's product folder and quality portal.