Texas Instruments LM22671MRX-5.0/NOPB

Overview

LM22671MRX-5.0/NOPB from Texas Instruments is a 42 V, 500 mA synchronous step-down DC/DC regulator with fixed 5.0 V output, 500 kHz switching frequency, ±1.5% feedback reference accuracy, and integrated 200 mΩ N-channel MOSFET. It operates across –40°C to 125°C and supports industrial power rails including 12 V and 24 V inputs.

For engineers reviewing the LM22671MRX-5.0/NOPB datasheet, LM22671MRX-5.0/NOPB pinout, LM22671MRX-5.0/NOPB application, or LM22671MRX-5.0/NOPB equivalent, key selection factors include input voltage range (4.5–42 V), thermal performance in HSOP-8 PowerPAD™, soft-start programmability, and compatibility with low-ESR ceramic output capacitors.

Technical Context

The LM22671MRX-5.0/NOPB implements voltage-mode PWM control with input voltage feed-forward for stable loop gain across wide VIN variations. Its internal Type III compensation is optimized for fixed 5 V output, eliminating external compensation components.

It integrates a bootstrap gate driver with dedicated BOOT/SW pins, precision enable with 1.6 V threshold and 0.6 V hysteresis, and selectable oscillator modes: internal 500 kHz default, resistor-adjustable (200 kHz–1 MHz), or external synchronization-though frequency adjustment and sync cannot operate simultaneously.

Key Specifications

Pinout & Package

LM22671MRX-5.0/NOPB is housed in an HSOP-8 package (4.89 mm × 3.90 mm) with exposed thermal pad (EP) that must be soldered to PCB ground for thermal management and EMI reduction.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM22670MRX-5.0/NOPB, LM22671MRX-5.0/NOPB trades lower VIN min for higher VIN max and automotive-grade thermal margin; versus TPS54302DDCR, it sacrifices current and frequency headroom for integration simplicity and ruggedness in harsh environments.

Availability

LM22671MRX-5.0/NOPB is available at Aetrix Electronics and suitable for industrial control, telecom/datacom systems, and embedded systems requiring stable component supply, long-term lifecycle assurance, and consistent parametric performance across temperature extremes.

Supply support for LM22671MRX-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 over 50 years of innovation in high-reliability power conversion.

The LM22671MRX-5.0/NOPB belongs to TI's SIMPLE SWITCHER® family-designed for ease-of-use in industrial, automotive, and communications applications where minimal external components, fast design-in, and robust operation under voltage transients are critical.

FAQ

What is the maximum input voltage rating for LM22671MRX-5.0/NOPB?

The absolute maximum input voltage for LM22671MRX-5.0/NOPB is 43 V, with recommended continuous operation from 4.5 V to 42 V. This 42 V rating enables direct connection to 24 V industrial buses with surge tolerance, and eliminates need for input overvoltage clamping in most applications. The device includes internal UVLO with 4.3 V turn-on threshold to prevent erratic startup during brownout conditions.

Does LM22671MRX-5.0/NOPB require external compensation components?

No, LM22671MRX-5.0/NOPB features fully internal Type III loop compensation optimized for its fixed 5.0 V output configuration. This eliminates external compensation networks, reduces design risk, and ensures stability with standard 4.7 µH inductors and 10–22 µF ceramic output capacitors. TI's WEBENCH® tool validates loop response during design, confirming phase margin >45° across line, load, and temperature.

How is thermal performance managed in the HSOP-8 PowerPAD™ package of LM22671MRX-5.0/NOPB?

LM22671MRX-5.0/NOPB uses an HSOP-8 package with exposed thermal pad (EP) that must be soldered to a large PCB copper pour connected to system ground. This achieves a junction-to-ambient thermal resistance (R_θJA) of 60°C/W. At 500 mA load and 42 V input, typical power dissipation is ~1.2 W; with proper thermal land pattern (≥200 mm²), junction temperature remains within –40°C to 125°C spec even in 70°C ambient.

Can LM22671MRX-5.0/NOPB synchronize to an external clock?

Yes, LM22671MRX-5.0/NOPB supports external clock synchronization via the RT/SYNC pin. When driven with a clean square wave (1.75–3.5 V amplitude, >500 kHz, <1 MHz), the device locks to the rising edge of the external signal. Synchronization is latched at startup and persists until EN or VIN is cycled. Note: current limit foldback is disabled during sync mode, so short-circuit protection relies solely on peak current limiting.

What is the purpose of the SS pin on LM22671MRX-5.0/NOPB, and how is it used?

The SS (soft-start) pin on LM22671MRX-5.0/NOPB controls output voltage ramp rate during startup. An external capacitor (100 nF–1 µF) between SS and GND extends the default ~500 µs soft-start time linearly with capacitance value. This prevents inrush current, limits input capacitor stress, and avoids false triggering of upstream current monitors. Soft-start resets automatically during shutdown or thermal fault, ensuring controlled restart under fault conditions.