Texas Instruments TPS25221DBVR

Overview

TPS25221DBVR from Texas Instruments is a 2.5-V to 5.5-V, 2-A continuous current-limited power-distribution switch with programmable overcurrent protection, 70-mΩ typical R_DS(on), 1.5-µs short-circuit response, and reverse-current blocking when disabled - deployed in USB ports, laptop docking stations, and set-top box power rails.

For engineers reviewing the TPS25221DBVR datasheet, TPS25221DBVR pinout, TPS25221DBVR application, or TPS25221DBVR equivalent, key selection criteria include adjustable current limit (275 mA–2.7 A via R_ILIM), 8-ms fault deglitching, thermal shutdown at 145°C/165°C, UL 60950/62368 recognition, and SOT-23-6 package compatibility with space-constrained USB Type-A/B port designs.

Technical Context

The TPS25221DBVR integrates an internal charge pump to drive its N-channel MOSFET gate above source potential, enabling full enhancement down to 2.5 V input while maintaining precise current regulation. Its current-sense amplifier monitors load current continuously and forces the FET into saturation during overloads to clamp I_OUT at the programmed IOS threshold.

It implements dual thermal protection: one sensor triggers at 145°C during sustained current-limit operation (with 20°C hysteresis), and another activates at 165°C for ambient overtemperature events. The FAULT pin uses unidirectional 8-ms deglitching - active only on overcurrent assertion - to suppress false triggers during capacitive inrush, while reporting overtemperature faults immediately.

Key Specifications

Pinout & Package

SOT-23-6 package (2.90 mm × 1.60 mm), thermally enhanced with exposed GND-connected pad for junction-to-board conduction (R_θJB = 65.6°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar current-limiting power switch applications.

Compared with TPS25221DBVR, TPS2553DBVR trades adjustability for simplicity and lower component count, while AP22653AW5-7 offers lower R_DS(on) and smaller size at the expense of safety certification and higher ESD susceptibility - making TPS25221DBVR optimal for certified USB consumer endpoints.

Availability

TPS25221DBVR is available at Aetrix Electronics and suitable for USB ports/hubs, laptop docking stations, and set-top box power rails requiring stable component supply, long-term lifecycle support, and traceable sourcing for production programs.

Supply support for TPS25221DBVR 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 ICs, embedded processors, and connectivity solutions for industrial, automotive, and consumer markets.

The TPS25221DBVR belongs to TI's precision power-distribution switch family, engineered specifically for USB-compliant hot-swap protection with programmable current limiting, thermal resilience, and safety certification - targeting high-reliability consumer electronics interfaces.

FAQ

What is the minimum input voltage required for TPS25221DBVR to operate?

The TPS25221DBVR requires a minimum input voltage of 2.37 V (UVLO rising threshold) to enable the internal power switch. Below this, the device remains disabled regardless of EN state. Operation is guaranteed across 2.5 V to 5.5 V per specifications, supporting both USB 2.0 (4.4–5.25 V) and low-voltage auxiliary rails. The TPS25221DBVR incorporates 45 mV hysteresis to prevent oscillation during input droop.

How do I calculate the R_ILIM resistor value for a 1.2-A current limit with TPS25221DBVR?

For a nominal 1.2-A current limit, use R_ILIM = 55.96 kΩ (from datasheet Figure 24 or Equation 1). Select a 1% tolerance metal-film resistor - e.g., 56.2 kΩ - which yields 1.19 A (within ±6.5% accuracy at mid-range). Place R_ILIM directly between ILIM (Pin 5) and GND with shortest possible traces to minimize parasitic inductance affecting accuracy. The TPS25221DBVR's ILIM pin regulates its own voltage to maintain proportionality.

Does TPS25221DBVR support reverse-current blocking when disabled?

Yes, the TPS25221DBVR provides active reverse-current blocking when EN is low: the internal N-channel MOSFET is fully turned off, preventing current flow from OUT to IN. This is confirmed in the Functional Description (Section 9.1) and Pin Functions table. Unlike passive diode solutions, this feature imposes no forward voltage drop during normal operation and eliminates leakage paths in battery-backed or multi-rail systems using the TPS25221DBVR.

What thermal derating applies to TPS25221DBVR at 85°C ambient temperature?

At 85°C ambient, the TPS25221DBVR's maximum continuous output current is reduced to ~1.4 A (calculated using R_θJA = 193.2°C/W and T_J(MAX) = 125°C). Derating follows: I_MAX = √[(T_J(MAX) − T_A) / (R_θJA × R_DS(on))]. With 70 mΩ R_DS(on), power dissipation must stay below 7.7 W. Layout with 2 oz copper and thermal vias under the pad restores >1.8 A capability. The TPS25221DBVR's thermal shutdown (145°C/165°C) provides hard fault protection beyond derating.

Can TPS25221DBVR be used in USB-C applications requiring 3-A current capability?

No - the TPS25221DBVR is rated for 2-A continuous current and 2.7-A peak limit. USB-C power delivery (PD) 3.0 requires up to 5 A at 20 V, far exceeding this device's voltage (5.5 V max) and current ratings. For USB-C applications, TI recommends the TPS6598x series PD controllers paired with discrete GaN or SiC switches. The TPS25221DBVR is strictly intended for legacy USB-A/B 5-V ports and downstream-facing hub ports per USB 2.0/3.2 Gen 1 specs.