Texas Instruments LMR36506R3RPER

Overview

LMR36506R3RPER from Texas Instruments is a 3.3V fixed-output, 0.6A synchronous buck converter in a 2mm × 2mm HotRod™ QFN (RPE) package, operating from 3V to 65V input with 4µA no-load quiescent current and 70V transient tolerance - deployed in field transmitters, HVAC controllers, and power tool battery management systems.

For engineers reviewing the LMR36506R3RPER datasheet, LMR36506R3RPER pinout, LMR36506R3RPER application, or LMR36506R3RPER equivalent, key selection criteria include its 3.3V fixed output accuracy (±1.5% in FPWM mode), PGOOD flag with 1.956ms activation delay, RT-programmable 200kHz–2.2MHz switching frequency, and –40°C to +150°C junction temperature rating for rugged industrial deployment.

Technical Context

The LMR36506R3RPER uses peak current mode control with internal compensation, enabling stable regulation with minimal external capacitance and eliminating need for loop compensation components. Its precision EN/UVLO threshold (1.263V typical) and hysteresis (0.35V) support reliable start-up sequencing in wide-input industrial rails.

It integrates high-side (920mΩ max) and low-side (460mΩ max) MOSFETs, supports auto-mode PFM operation at light load for ultra-low IQ, and features thermal shutdown (168°C rising) with 10°C hysteresis. The PGOOD pin provides glitch-filtered status with 25µs filter time constant and 94–96.5% falling threshold relative to VOUT/BIAS.

Key Specifications

Pinout & Package

LMR36506R3RPER is housed in a 2mm × 2mm, 9-pin VQFN-HR (HotRod™) package with exposed thermal pad (RPE). The package supports high-density PCB layouts and enhanced thermal performance via direct die-to-board conduction.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous buck converter applications.

Compared with LMR36506RFRPER, LMR36506R3RPER delivers tighter 3.3V accuracy without external components; versus LMR36503R3RPER, it doubles output current capacity while retaining identical footprint and thermal characteristics - making it optimal for next-gen industrial edge nodes requiring higher processing power.

Availability

LMR36506R3RPER is available at Aetrix Electronics and suitable for factory automation sensors, building HVAC controllers, and garden power tool battery management systems requiring stable component supply across long product lifecycles and harsh environmental conditions.

Supply support for LMR36506R3RPER 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 industrial-grade reliability validation.

The LMR36506R3RPER belongs to TI's LMR365xx family of ultra-small, high-voltage buck converters designed specifically for rugged industrial power rails - emphasizing low IQ, transient robustness, and minimal external component count.

FAQ

What is the guaranteed output voltage accuracy of LMR36506R3RPER at full load and over temperature?

The LMR36506R3RPER guarantees ±1.5% output voltage accuracy for its 3.3V fixed output in FPWM mode across the full –40°C to +150°C junction temperature range and 0–0.6A load. This specification is validated per Electrical Characteristics Table 6.8 and applies to nominal input voltages from 3.6V to 65V, ensuring consistent MCU and sensor biasing in demanding thermal environments.

Does LMR36506R3RPER support external synchronization of its switching frequency?

No, LMR36506R3RPER does not support external synchronization. It features an RT pin for resistor-programmable frequency (200kHz–2.2MHz) but lacks a MODE/SYNC pin. Synchronization capability is reserved for other variants like LMR36506RF3RPER with FPWM default mode - LMR36506R3RPER operates in auto-mode PFM by default and cannot accept external clock signals.

Can LMR36506R3RPER be used with input voltages below 3.0V?

No, LMR36506R3RPER is not functional below 3.0V input. Its minimum operating input voltage (falling threshold) is specified as 2.45V (typical) to 3.0V (max), but startup requires ≥3.4V (rising threshold). Operation below 3.6V is outside recommended conditions per Section 6.3, and output regulation cannot be guaranteed - use only within 3.6V–65V for production designs.

How is thermal performance characterized for LMR36506R3RPER in the RPE package?

LMR36506R3RPER's thermal performance in the 2mm × 2mm RPE package is characterized with RθJA = 84.4°C/W (JEDEC 4-layer board), RθJB = 26.1°C/W, and RθJC(top) = 47.5°C/W. These metrics confirm suitability for high-power-density layouts; derating is required above 125°C junction temperature, and thermal shutdown activates at 168°C (rising) with 10°C hysteresis to protect against sustained overload.

Is the PGOOD output of LMR36506R3RPER compatible with 5V logic systems?

Yes, the open-drain PGOOD output of LMR36506R3RPER is compatible with 5V logic. Its RDS(ON) is 20–40Ω when enabled (VEN = 5.0V, 1mA pull-up), allowing direct connection to 5V microcontrollers with standard pull-up resistors. The pin remains low during startup, fault conditions, or EN deactivation - providing unambiguous system status indication without level-shifting.