Texas Instruments LM22671QMR-5.0/NOPB

Overview

LM22671QMR-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 from 4.5 V to 42 V input and delivers stable power in industrial control and telecom systems requiring compact, high-efficiency buck conversion.

For engineers reviewing the LM22671QMR-5.0/NOPB datasheet, LM22671QMR-5.0/NOPB pinout, LM22671QMR-5.0/NOPB application, or LM22671QMR-5.0/NOPB equivalent, key selection criteria include its automotive-grade AEC-Q100 Grade 1 qualification (–40°C to +125°C), internal voltage-mode compensation, precision enable threshold (1.6 V typ), adjustable soft-start via external capacitor, and compatibility with low-ESR ceramic output capacitors.

Technical Context

The LM22671QMR-5.0/NOPB implements a voltage-mode PWM controller with input voltage feed-forward to stabilize loop gain across wide VIN ranges. Its internal Type III compensation network is optimized for fixed 5 V output and eliminates need for external compensation components.

It integrates a bootstrap gate driver with dedicated BOOT/SW pins to drive the high-side N-MOSFET, requires no external bootstrap diode, and enforces minimum on-time (100 ns) and off-time (100 ns) to ensure boot-capacitor recharge and stable operation at high duty-cycle ratios.

Key Specifications

Pinout & Package

LM22671QMR-5.0/NOPB uses an HSOP-8 package (4.89 mm × 3.90 mm) with exposed thermal pad (EP) that must be soldered to PCB ground for thermal performance and EMI reduction.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM22671QMR-5.0/NOPB, LM22670QMR-5.0/NOPB offers slightly better efficiency at light loads but reduced input surge tolerance, while TPS54302DDCR provides triple the current capability at the cost of added external components and no automotive qualification-making LM22671QMR-5.0/NOPB optimal for space- and reliability-constrained 500 mA automotive/industrial buck applications.

Availability

LM22671QMR-5.0/NOPB is available at Aetrix Electronics and suitable for industrial control, automotive body electronics, and telecom power conversion requiring stable component supply, long-term lifecycle support, and AEC-Q100 compliance.

Supply support for LM22671QMR-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 designing analog and embedded processing solutions for industrial, automotive, and communications markets.

The LM22671 product line delivers SIMPLE SWITCHER® buck regulators targeting high-reliability, low-component-count DC/DC conversion in harsh environments-from factory floors to vehicle cabins.

FAQ

What is the maximum input voltage rating for LM22671QMR-5.0/NOPB?

The LM22671QMR-5.0/NOPB has an absolute maximum input voltage rating of 43 V, with recommended continuous operation from 4.5 V to 42 V. This 42 V upper limit ensures robustness against automotive load-dump transients and industrial 24 V rail surges. The device maintains regulation and protection functionality-including thermal shutdown and current limiting-throughout this full range. Exceeding 43 V may cause permanent damage per the Absolute Maximum Ratings table in the SNVS589N datasheet.

Does LM22671QMR-5.0/NOPB require an external feedback resistor divider?

No, LM22671QMR-5.0/NOPB does not require an external feedback resistor divider. It is the fixed 5.0 V output variant: the FB pin is internally connected to the regulated output, eliminating external resistors and associated layout sensitivity. This simplifies design, improves accuracy (±1.5% over temperature), and reduces BOM cost versus adjustable versions like LM22671-ADJ. The internal reference and error amplifier are factory-trimmed specifically for 5.0 V regulation.

Can LM22671QMR-5.0/NOPB synchronize to an external clock?

Yes, LM22671QMR-5.0/NOPB can synchronize to an external clock via the RT/SYNC pin. When driven with a clean square wave ≥500 kHz and ≤1 MHz, with amplitude meeting VSYNC thresholds (1.75 V min high, 0.25 V max low), the device locks to the rising edge of the external signal. Synchronization disables current-limit foldback but enables EMI reduction and multi-regulator phase alignment. Mode selection occurs at startup and remains latched until EN or VIN is cycled.

What thermal pad connection is required for LM22671QMR-5.0/NOPB?

The exposed thermal pad (EP) on LM22671QMR-5.0/NOPB must be soldered directly to a solid PCB ground plane using ≥4 thermal vias (0.3 mm diameter) to inner/ground layers. This connection provides the primary thermal path-reducing θ_JA from 60°C/W (no pad connection) to <30°C/W in typical layouts-and also lowers EMI by shielding the switch node. Leaving the pad unconnected degrades thermal performance and may trigger premature thermal shutdown under 500 mA load at elevated ambient temperatures.

Is LM22671QMR-5.0/NOPB qualified for automotive applications?

Yes, LM22671QMR-5.0/NOPB is the automotive-grade variant (denoted by "Q" suffix and "Q1" in documentation), certified to AEC-Q100 Grade 1 standards for operation from –40°C to +125°C junction temperature. It undergoes additional stress testing including HTOL, temperature cycling, and ESD validation per JESD22. The "/NOPB" suffix confirms lead-free, RoHS-compliant packaging. This qualification makes LM22671QMR-5.0/NOPB suitable for body control modules, infotainment power supplies, and ADAS sensor hubs where reliability under thermal and vibration stress is critical.