Texas Instruments LMR36015ARNXR

Overview

LMR36015ARNXR from Texas Instruments is a 4.2-V to 60-V, 1.5-A synchronous step-down DC/DC converter in a 2-mm × 3-mm HotRod™ VQFN-HR package. It delivers regulated output with peak-current-mode control, supports 400-kHz fixed switching frequency, features 26-µA quiescent current in PFM mode, and withstands 66-V input transients-ideal for industrial field transmitters and PLC modules.

For engineers reviewing the LMR36015ARNXR datasheet, LMR36015ARNXR pinout, LMR36015ARNXR application, or LMR36015ARNXR equivalent, key selection criteria include input transient tolerance (66 V), thermal robustness (–40°C to +150°C junction), power-good flag timing (80–200 µs deglitch), adjustable output via FB pin (1.0 V reference), and EMI-optimized layout with parallel input path and spread spectrum.

Technical Context

The LMR36015ARNXR uses peak-current-mode control with internal loop compensation, enabling stable regulation across 4.2–60 V input without external compensation components. Its auto-mode operation transitions between PWM (fixed 400 kHz) at heavy loads and PFM (diode-emulation DCM) at light loads to maintain >90% efficiency at 1 A and 24 V_IN/5 V_OUT.

It integrates high-side and low-side MOSFETs with R_DS(on) of 225–435 mΩ (HS) and 150–280 mΩ (LS), supports precision enable thresholds (VEN-H = 1.231 V typ.), and provides a filtered open-drain power-good flag with 93–95% lower threshold and 105–110% upper threshold relative to 1.0-V feedback reference.

Key Specifications

Pinout & Package

LMR36015ARNXR is housed in a 12-pin VQFN-HR (RNX) package measuring 2.00 mm × 3.00 mm with wettable flanks, optimized for thermal performance (R_θJA = 72.5°C/W) and ultra-low EMI via flip-chip HotRod™ construction.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LMR36015ARNXR, LMR36006ARNXR trades output current for lower cost in low-power roles, while LMR33630BRNXR increases current capability at the expense of input voltage range and requires layout revision due to non-pin-compatible pinout.

Availability

LMR36015ARNXR is available at Aetrix Electronics and suitable for industrial field transmitters, PLC I/O modules, HVAC control units, and industrial video surveillance systems requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for LMR36015ARNXR 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 industrial and automotive power solutions.

The LMR360xx family was designed specifically for scalable, space-constrained industrial power supplies-delivering rugged 60-V operation, ultra-low EMI, and seamless PFM/PWM transition in sub-3-mm² packages.

FAQ

What is the maximum input voltage the LMR36015ARNXR can withstand without damage?

The LMR36015ARNXR has an absolute maximum input voltage rating of 66 V, meaning it can survive transient overvoltages up to this level without permanent damage. Its recommended operating input range is 4.2 V to 60 V. This 66-V tolerance satisfies IEC 61000-4-5 surge immunity requirements and eliminates the need for external TVS diodes in many industrial 24-V and 48-V applications. Always ensure continuous operation remains within the 60-V limit specified in Recommended Operating Conditions.

Does the LMR36015ARNXR support adjustable output voltage, and how is it configured?

Yes, the LMR36015ARNXR supports fully adjustable output voltage via its FB pin, which references an internal 1.000-V ±15-mV precision bandgap. Output voltage is set using a two-resistor feedback divider from V_OUT to AGND, with the tap connected to FB. For example, a 100-kΩ top resistor and 102-kΩ bottom resistor yields approximately 3.3 V. The device does not include internal resistors-external division is mandatory-and the FB pin leakage is only 0.2 nA, ensuring minimal error contribution from divider current.

How does the power-good (PG) flag on the LMR36015ARNXR behave during startup and fault conditions?

The LMR36015ARNXR's open-drain PG flag goes high ≈4 ms after EN is asserted, once V_OUT reaches 105% of the target (e.g., 5.25 V for 5-V output). It remains high as long as V_OUT stays between 93% and 110% of the nominal value, with built-in 80–200 µs deglitching to reject transients. During faults-including thermal shutdown, current limit, or EN deactivation-the PG pin pulls low. When EN is low, PG stays valid down to 2 V input, enabling reliable system reset sequencing even during brownout conditions.

What thermal performance can be expected from the LMR36015ARNXR in a standard 2-layer PCB layout?

In a typical 2-layer PCB with 1-in² 2-oz copper pads connected to PGND and VIN pins, the LMR36015ARNXR achieves a junction-to-ambient thermal resistance (R_θJA) of 72.5°C/W. At 1.5-A load and 24-V input, power dissipation is ~0.5 W, resulting in ≈36°C junction rise above ambient. With proper thermal vias under the exposed pad and minimal trace length, the device reliably operates up to its full +150°C junction rating. Thermal shutdown activates at 170°C, with recovery at 158°C, providing robust protection during overload or poor airflow scenarios.

Is the LMR36015ARNXR pin-compatible with other members of the LMR360xx family, and what does that mean for design reuse?

Yes, the LMR36015ARNXR is pin-compatible with the LMR36006 (0.6-A variant) in the same VQFN-HR package, enabling direct substitution in existing layouts when lower output current is acceptable. However, it is not pin-compatible with the 1-MHz variants (e.g., LMR36015FBRNXR) or the LMR336xx series-those have different pin functions (e.g., SW placement) despite identical footprint dimensions. Pin compatibility applies only to same-frequency, same-package variants; always verify EN thresholds, current limits, and thermal behavior before drop-in replacement.