Texas Instruments TPS7425D

Overview

TPS7425D from Texas Instruments is a 200-mA, 2.5-V fixed-output low-dropout (LDO) voltage regulator in an 8-pin SOIC package, featuring 170 mV dropout at 200 mA (typ.), ±3% output voltage tolerance over line/load/temperature, and fast transient response stable with 1-µF output capacitors. It serves as a precision power supply for noise-sensitive analog circuitry and low-voltage microcontrollers in portable instrumentation.

For engineers reviewing the TPS7425D datasheet, TPS7425D pinout, TPS7425D application, or TPS7425D equivalent, key selection criteria include dropout performance at full load, thermal shutdown behavior, enable-input logic thresholds, output noise (190 µV_RMS), and compatibility with low-ESR ceramic capacitors down to 1 µF.

Technical Context

The TPS7425D employs a PMOS pass transistor architecture that enables ultra-low dropout voltage and eliminates reverse-current flow during input brownout. Its internal error amplifier uses a high-impedance SENSE terminal for remote sensing capability, supporting precise regulation at point-of-load despite PCB trace resistance.

Stability is achieved with output capacitors as low as 1 µF and ESR ≥ 300 mΩ-enabling compact designs without bulk electrolytics. The device integrates thermal shutdown (150°C trip), current limiting (~500 mA), and TTL-compatible enable control with <1 µA standby current when disabled.

Key Specifications

Pinout & Package

TPS7425D is housed in an 8-pin SOIC (D) package (JEDEC MS-012, AA variant), 3.91 mm × 4.90 mm footprint, 1.75 mm max height, RoHS-compliant NIPDAU lead finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS7425D, TPS76325DBVR trades remote sensing and lower dropout for smaller footprint, while MCP1702T-2502E/MB sacrifices enable functionality and thermal protection for ultra-low quiescent current and lower BOM cost - neither offers identical feature parity.

Availability

TPS7425D is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, wearables with low-power MCUs, and automotive body control units requiring stable component supply with guaranteed long-term manufacturability.

Supply support for TPS7425D 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 connectivity technologies, with decades of expertise in power management IC design and high-reliability manufacturing.

The TPS74xx family was engineered for high-accuracy, low-noise power delivery in space- and power-constrained applications - particularly targeting portable instrumentation, industrial automation, and automotive subsystems demanding fast transient response and robust thermal behavior.

FAQ

What is the minimum input voltage required for stable operation of the TPS7425D?

The minimum input voltage for the TPS7425D is calculated as VO(max) + VDO(max). With a 2.5-V nominal output and maximum dropout of 350 mV (over temperature), VI(min) = 2.575 V + 0.35 V = 2.925 V. Per datasheet, the absolute minimum specified VI is 3.5 V for 2.5-V output variants - ensuring margin for worst-case tolerance and dropout. Therefore, 3.5 V is the recommended minimum input voltage for guaranteed 200-mA operation across –40°C to 125°C.

Can the TPS7425D be used without connecting the SENSE pin?

No - the SENSE pin is mandatory for proper regulation in the TPS7425D. Datasheet Section "SENSE terminal connection" explicitly states it "must be connected to the regulator output for proper functioning." Leaving SENSE unconnected causes unstable output voltage and potential oscillation. For local regulation, connect SENSE directly to the OUT pin; for remote sensing, route it to the load-side of the output capacitor with minimal noise pickup.

Does the TPS7425D support ceramic output capacitors below 10 µF?

Yes - the TPS7425D is specifically characterized for stability with 1-µF ceramic capacitors (X7R/X5R), provided ESR is ≥300 mΩ. Figure 19 confirms stable operation across 1–200 mA load range with 1 µF. Using smaller values (e.g., 470 nF) risks instability, while larger ceramics (>10 µF) are acceptable but offer diminishing returns on transient response improvement.

What happens to the TPS7425D output when input voltage drops below the output voltage?

When VI falls below VO, the internal PMOS pass transistor's body diode conducts reverse current from OUT to IN. This is not current-limited by the TPS7425D and may cause backfeeding or damage to upstream circuitry. The datasheet advises adding external reverse-current protection (e.g., series Schottky diode) if extended reverse voltage is anticipated - especially during power-down sequences or hot-swap events.

Is the TPS7425D pin-compatible with other members of the TPS74xx family?

Yes - all TPS74xx devices (TPS7415D, TPS7418D, TPS7425D, TPS7430D, TPS7433D) share identical 8-pin SOIC (D) packages and pinouts. The only differences are output voltage and corresponding part marking (e.g., "7425" on top). This allows direct voltage-scaling substitutions in existing designs without layout changes, provided input voltage headroom and load requirements align with the new output voltage.