Texas Instruments TPS78925DBVTG4

Overview

TPS78925DBVTG4 from Texas Instruments is a 2.5-V, 100-mA ultralow-power, low-noise LDO voltage regulator in a 5-pin SOT-23 (DBV) package. It features 2.5 V ±2.5% output accuracy over –40°C to 125°C, 115 mV typical dropout at 100 mA, 17 µA quiescent current, and 56 µVRMS output noise (measured on TPS78930 with same architecture). It is used in battery-powered portable electronics requiring stable low-noise bias for RF front-ends and precision analog circuitry.

For engineers reviewing the TPS78925DBVTG4 datasheet, TPS78925DBVTG4 pinout, TPS78925DBVTG4 application, or TPS78925DBVTG4 equivalent, key selection criteria include its PMOS pass element enabling ultra-low dropout, BYPASS pin for noise filtering, enable-controlled 1 µA standby mode, and compatibility with 4.7 µF minimum output capacitance for stability in space-constrained designs.

Technical Context

The TPS78925DBVTG4 employs a PMOS pass transistor instead of conventional PNP, eliminating drive-current dependency on load and delivering dropout voltage directly proportional to output current. Its internal 150-kΩ resistor and external BYPASS capacitor form a configurable low-pass filter that suppresses reference noise - critical for achieving sub-60 µVRMS output noise.

It integrates thermal shutdown (trip ~165°C, hysteresis ~25°C) and current limiting (~350 mA), with reverse-current conduction via the PMOS body diode when VIN < VOUT. The EN pin has no intentional hysteresis and switches at ~1.5 V, disabling regulation and reducing ground current to 1 µA.

Key Specifications

Pinout & Package

TPS78925DBVTG4 is housed in a 5-pin SOT-23 (DBV) package - 2.9 mm × 1.6 mm × 1.1 mm, surface-mount, RoHS-compliant, moisture sensitivity level 1 (260°C peak reflow).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-noise, low-quiescent-current LDO applications.

Compared with TPS78925DBVTG4, TPS78925DBVR offers identical performance in higher-volume packaging, while MCP1702T-2502E/MB trades noise filtering capability for lower quiescent current - making it viable only where spectral purity is not critical.

Availability

TPS78925DBVTG4 is available at Aetrix Electronics and suitable for wireless sensor nodes, portable medical instrumentation, and wearable fitness trackers requiring stable component supply with guaranteed long-term sourcing.

Supply support for TPS78925DBVTG4 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 and embedded processing technologies, with decades of expertise in power management ICs.

The TPS789xx family was designed specifically for battery-powered portable equipment demanding ultralow dropout, low-noise regulation, and minimal quiescent current - targeting extended runtime and signal integrity in space-constrained applications.

FAQ

What is the minimum input voltage required for TPS78925DBVTG4 to maintain regulation at 100 mA?

The minimum input voltage for TPS78925DBVTG4 is VO(typ) + 1 V = 3.5 V under recommended operating conditions. At 100 mA load and 25°C, its typical dropout is 115 mV, so regulation is maintained down to ~2.615 V - but per datasheet, 3.5 V is the specified minimum to guarantee performance across temperature and process variation. Operating below 3.5 V risks loss of regulation or increased noise.

Does TPS78925DBVTG4 support reverse current protection?

TPS78925DBVTG4 does not include active reverse-current blocking. Its PMOS pass element contains an intrinsic body diode that conducts from OUT to IN when VIN falls below VOUT - for example, during power-down sequencing. This can cause backfeed into upstream supplies. External solutions like a series Schottky diode or ideal diode controller are required if reverse-current prevention is mandatory in the system design.

How does the BYPASS pin affect startup time and noise performance in TPS78925DBVTG4?

The BYPASS pin connects internally to the voltage reference through a 150-kΩ resistor. Adding an external capacitor creates an RC filter: larger capacitance lowers noise but increases startup time due to the RC time constant. For example, 0.01 µF yields ~56 µVRMS noise and fast startup, while 0.1 µF further reduces noise but slows turn-on - a trade-off explicitly documented in the TPS78925DBVTG4 datasheet.

What output capacitor specifications are mandatory for stable operation of TPS78925DBVTG4?

TPS78925DBVTG4 requires a minimum 4.7 µF output capacitor with ESR between 0.2 Ω and 10 Ω for guaranteed stability. Ceramic, tantalum, and aluminum electrolytic types are acceptable if they meet this ESR window. Capacitors below 4.7 µF risk oscillation; those above are allowed and relax ESR constraints. Solid tantalum parts like KEMET T494B475K016AS (4.7 µF, 1.5 Ω ESR) are validated for use with TPS78925DBVTG4.

Is TPS78925DBVTG4 pin-compatible with other members of the TPS789xx family?

Yes, all TPS789xx variants - including TPS78915DBVTG4, TPS78918DBVTG4, TPS78925DBVTG4, TPS78928DBVTG4, and TPS78930DBVTG4 - share identical 5-pin SOT-23 (DBV) packaging and pinout. They differ only in fixed output voltage and part marking (PDWI, PDXI, PDYI, PDZI, PEAI). This allows drop-in replacement across voltage points without PCB changes, provided input voltage headroom and load requirements are met.