Texas Instruments LM25066IAPSQ/NOPB

Overview

LM25066IAPSQ/NOPB from Texas Instruments is an Intel Node Manager 2.0/2.5-compliant system power management and protection IC with PMBus™ interface. It integrates hot-swap control, real-time telemetry (VIN, IIN, PIN, VOUT, VAUX, temperature), programmable current/power limiting, and circuit breaker protection for 2.9V–17V input systems. Used in server backplanes and solid-state eFuses to prevent inrush damage and enable intelligent power monitoring.

For engineers reviewing the LM25066IAPSQ/NOPB datasheet, LM25066IAPSQ/NOPB pinout, LM25066IAPSQ/NOPB application, or LM25066IAPSQ/NOPB equivalent, this page delivers verified technical context, exact pin functions, Intel NM–compliant telemetry accuracy (±1% IIN, ±2.0% PIN), black-box fault capture, and hardware-configurable UVLO/OVLO hysteresis - all critical for server power rail design and PMBus-based system management.

Technical Context

The LM25066IAPSQ/NOPB implements a dual-stage protection architecture: first, a controlled insertion delay (via TIMER pin capacitor) prevents inrush transients; second, simultaneous current-limiting (25mV/46mV thresholds) and power-limiting (PWR pin resistor-set) enforce MOSFET SOA compliance. Its 12-bit ADC samples VIN, IIN, PIN, VOUT at 1 kHz with averaging over 0.001–4 s intervals.

It features Intel Node Manager–compliant PMBus 1.2 communication via SMBus/I²C, supporting READ_EIN for true energy accumulation, WARN/FAULT threshold programming, and SMBA alert signaling. The device includes a black-box telemetry snapshot triggered by WARN or FAULT events, capturing real-time VIN, IIN, PIN, VOUT, VAUX, temperature, and status registers.

Key Specifications

Pinout & Package

LM25066IAPSQ/NOPB uses a 5 mm × 4 mm WQFN-24 package with exposed thermal pad soldered to ground plane for optimal thermal performance (θJA = 42.3°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar system power management applications.

Compared with LM25066IA, the LM25066IAPSQ/NOPB trades minor telemetry accuracy for identical Node Manager functionality and lower cost; versus TPS2491, it adds full PMBus telemetry, energy accumulation, and fault diagnostics - making it essential for datacenter-grade power management.

Availability

LM25066IAPSQ/NOPB is available at Aetrix Electronics and suitable for server backplane systems, basestation power distribution systems, and solid-state circuit breaker (eFuse) designs requiring stable component supply, long-term lifecycle support, and Intel Node Manager compliance.

Supply support for LM25066IAPSQ/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 delivering analog and embedded processing solutions, with deep expertise in power management ICs for datacenter, industrial, and communications infrastructure.

The LM25066IAPSQ/NOPB belongs to TI's Node Manager–compliant hot-swap controller family, designed specifically for intelligent, standards-based power monitoring and protection in high-availability server and telecom systems.

FAQ

What is the primary function of the LM25066IAPSQ/NOPB in a server power architecture?

The LM25066IAPSQ/NOPB serves as an Intel Node Manager–compliant hot-swap controller and power telemetry IC. It manages inrush current during blade insertion, enforces programmable current and power limits on the external MOSFET, monitors real-time VIN, IIN, PIN, VOUT, VAUX, and temperature via PMBus, and provides black-box fault capture - all critical for server backplane reliability and BMC-based power management. The LM25066IAPSQ/NOPB replaces discrete protection circuits with integrated, standards-aligned intelligence.

How does the LM25066IAPSQ/NOPB implement hardware-configurable protection without firmware?

The LM25066IAPSQ/NOPB uses dedicated pins - CL (current limit range), CB (circuit breaker scaling), RETRY (fault recovery mode), UVLO/EN and OVLO (voltage lockout thresholds) - to configure protection behavior directly via external resistors or logic levels. For example, tying CL to GND sets a 25mV current limit, while connecting CB to VDD configures the circuit breaker to trip at 3.6× that limit. This allows deterministic, fail-safe operation independent of PMBus communication. The LM25066IAPSQ/NOPB maintains these settings even during host processor boot or failure.

What telemetry data does the LM25066IAPSQ/NOPB provide, and how is it accessed?

The LM25066IAPSQ/NOPB provides real-time 12-bit telemetry for VIN, VOUT, IIN, PIN, VAUX, and temperature (via external diode), sampled at 1 kHz with hardware-averaging over 1 ms–4 s intervals. Data is accessed via PMBus commands including READ_VIN, READ_IIN, READ_PIN, READ_TEMPERATURE_1, and the Node Manager–specific READ_EIN for true energy accumulation. All telemetry supports WARN/FAULT threshold programming and SMBA alert generation. The LM25066IAPSQ/NOPB also captures a black-box snapshot of all telemetry and status registers upon WARN or FAULT assertion.

Is the LM25066IAPSQ/NOPB pin-compatible with other devices in the LM25066 family?

Yes, the LM25066IAPSQ/NOPB is pin-compatible with the LM25066IA variant - sharing identical WQFN-24 footprint, pin assignments, and electrical interface. Both support the same PMBus command set, hardware configuration pins (CL, CB, RETRY, etc.), and functional block diagram. However, the LM25066IA offers tighter current (±1%) and power (±2.0%) measurement accuracy over temperature. No PCB changes are required when substituting LM25066IAPSQ/NOPB with LM25066IA or vice versa.

What thermal management features does the LM25066IAPSQ/NOPB support?

The LM25066IAPSQ/NOPB supports thermal monitoring via its DIODE pin, which interfaces with an external NPN transistor configured as a remote diode sensor to estimate MOSFET junction temperature. It provides 9-bit remote diode resolution and ±2°C to ±10°C accuracy depending on implementation. Additionally, the device itself operates from −40°C to +125°C junction temperature and includes thermal shutdown protection. The exposed pad in the WQFN-24 package must be soldered to a thermal ground plane (θJA = 42.3°C/W) to maintain safe operating temperatures under full load. The LM25066IAPSQ/NOPB uses this thermal data to trigger WARN/FAULT thresholds and enable thermal-aware power limiting.