Texas Instruments LMR23625CFPDRRR

Overview

LMR23625CFPDRRR from Texas Instruments is a 36-V, 2.5-A synchronous step-down DC-DC converter in a 12-pin WSON wettable flanks package with PowerPAD™. It delivers regulated output from 4 V to 36 V input, supports fixed 2.1-MHz forced-PWM operation, integrates high- and low-side MOSFETs (R_DS(on) = 160 mΩ / 95 mΩ), and features PGOOD flag, precision enable, and hiccup-mode short-circuit protection. It targets industrial power conditioning in PLC CPU and HVAC control systems.

For engineers reviewing the LMR23625CFPDRRR datasheet, LMR23625CFPDRRR pinout, LMR23625CFPDRRR application, or LMR23625CFPDRRR equivalent, key selection considerations include its 2.1-MHz FPWM-only operation, 12-pin WSON thermal performance (R_θJA = 41.5°C/W), integrated PGOOD, 75-µA quiescent current, and compatibility with WEBENCH® Power Designer for custom design.

Technical Context

The LMR23625CFPDRRR employs fixed-frequency peak-current-mode control with internal compensation, eliminating external loop components. Its 2.1-MHz switching frequency is fixed (FPWM only) and synchronizable to an external clock (200–2200 kHz), enabling EMI reduction in noise-sensitive environments.

It integrates both high-side and low-side NMOS switches with verified R_DS(on) values of 160 mΩ and 95 mΩ at VIN = 12 V, I_OUT = 1 A. Protection includes cycle-by-cycle current limiting (HS peak limit = 4.0–6.6 A), thermal shutdown (162–178°C), and hiccup-mode recovery (10-ms retry delay).

Key Specifications

Pinout & Package

LMR23625CFPDRRR uses a 12-pin WSON (DRR) package with wettable flanks and exposed thermal pad (Pin 9). The package measures 3.00 mm × 3.00 mm and requires solder paste stencil optimization for reliable reflow of side-wettable leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LMR23625CFDDA, LMR23625CFPDRRR offers superior EMI control and system-level monitoring via PGOOD but sacrifices PFM flexibility. Against LMR23630CFPDRRR, it trades 0.5-A headroom for lower conduction loss at typical loads and reduced thermal stress in constrained layouts.

Availability

LMR23625CFPDRRR is available at Aetrix Electronics and suitable for factory automation, building HVAC control, and fleet telematics requiring stable component supply, long-term industrial lifecycle support, and consistent WSON wettable flanks manufacturing quality.

Supply support for LMR23625CFPDRRR 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 deep expertise in industrial-grade DC-DC conversion.

The LMR23625CFPDRRR belongs to TI's SIMPLE SWITCHER® family of easy-to-use synchronous buck regulators, designed specifically for robust, low-component-count power solutions in harsh industrial environments.

FAQ

What is the switching frequency configuration of the LMR23625CFPDRRR?

The LMR23625CFPDRRR operates exclusively in forced-PWM (FPWM) mode at a fixed 2.1-MHz switching frequency. Unlike other variants such as LMR23625CFDDA, it does not support PFM mode. This ensures constant frequency operation and minimal output voltage ripple across all load conditions, making it ideal for noise-sensitive applications like sensor signal chains and RF modules.

Does the LMR23625CFPDRRR support external frequency synchronization?

Yes, the LMR23625CFPDRRR supports external clock synchronization via its EN/SYNC pin. An AC-coupled external clock signal (200–2200 kHz, 2.8–5.5 V amplitude) can be applied to align switching edges with system clocks or reduce EMI through spread-spectrum techniques. This capability is retained despite the device's FPWM-only operation and is documented in Section 6.7 and 7.3.3 of the datasheet.

What is the purpose of the PGOOD pin on the LMR23625CFPDRRR?

The PGOOD pin on the LMR23625CFPDRRR is an open-drain power-good flag that asserts high when the output voltage is within ±4% to ±6% of the target (92–96.5% UV, 104–110% OV thresholds relative to 1.0-V reference). It enables reliable system power sequencing, processor reset coordination, and fault detection without external supervision circuitry - a key differentiator from the HSOIC variant LMR23625CFDDA, which lacks this pin.

How does the thermal performance of the LMR23625CFPDRRR compare to the HSOIC version?

The LMR23625CFPDRRR in 12-pin WSON achieves R_θJA = 41.5°C/W, slightly better than the 8-pin HSOIC variant's 42.0°C/W. Its lower R_θJC(bot) (3.4°C/W vs. 3.6°C/W) reflects more efficient heat transfer through the exposed thermal pad to the PCB ground plane. Full thermal performance requires proper soldering of the thermal pad to ≥200 mm² of inner-layer copper, per TI's layout guidelines in Section 10.4.

Can the LMR23625CFPDRRR start up into a prebiased output?

Yes, the LMR23625CFPDRRR supports soft-start into a prebiased load. Its internal soft-start circuitry prevents reverse current flow during startup when the output voltage is already present - a critical feature for hot-swap applications, redundant power systems, and systems with large hold-up capacitance. This behavior is enabled by default and requires no external components or configuration.