Texas Instruments TPS79425DGNRG4

Overview

TPS79425DGNRG4 from Texas Instruments is a 2.5V fixed-output, 250mA low-dropout linear regulator in HVSSOP-8 (DGN) package with enable input, 155mV typical dropout at full load, 60dB PSRR at 10kHz, and stable operation with only 2.2µF ceramic output capacitor - used for powering noise-sensitive analog circuitry in portable RF electronics and smart peripherals.

For engineers reviewing the TPS79425DGNRG4 datasheet, TPS79425DGNRG4 pinout, TPS79425DGNRG4 application, or TPS79425DGNRG4 equivalent, key selection criteria include dropout voltage under 250mA load, PSRR performance above 10kHz, thermal behavior in HVSSOP-8, and compatibility with low-ESR ceramic capacitors without external compensation.

Technical Context

The TPS79425DGNRG4 implements a PMOS pass transistor architecture enabling ultra-low dropout and inherent reverse-current blocking. Its internal 1.225V bandgap reference feeds a precision error amplifier that drives the pass element with fast transient response-achieving <50µs start-up time and sub-10mV load regulation across 0–250mA.

It integrates undervoltage lockout (UVLO) with 1.32V–1.6V threshold (new chip), active discharge via internal pulldown MOSFET during shutdown, and hybrid brickwall-foldback current limiting (320–460mA ICL, 175mA ISC) to protect against short-circuit and thermal overload conditions.

Key Specifications

Pinout & Package

HVSSOP-8 (DGN) package: 3mm × 4.9mm body with exposed thermal pad (Pin 5), optimized for high-power-density layouts and thermal performance on 2-layer PCBs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS79425DGNT, the TPS79425DGNRG4 offers identical performance in a different packaging format; versus TPS7A2025PDQNR, it trades higher IQ for enable functionality, active discharge, and superior transient response - making it preferable in systems requiring controlled power sequencing and dynamic load handling.

Availability

TPS79425DGNRG4 is available at Aetrix Electronics and suitable for smartphone baseband power, industrial sensor node regulation, and connected peripheral supply requiring stable component supply with guaranteed long-term sourcing.

Supply support for TPS79425DGNRG4 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 broad industrial, automotive, and communications portfolio coverage.

The TPS794 family was designed for noise-sensitive analog and RF applications demanding high PSRR, low dropout, and fast transient response - particularly in space-constrained portable electronics where ceramic capacitor compatibility and thermal efficiency are critical.

FAQ

What is the maximum input voltage rating for the TPS79425DGNRG4?

The TPS79425DGNRG4 has an absolute maximum input voltage of 6.5V for the new chip revision. Operation above 5.5V violates recommended conditions and risks permanent damage. For reliable operation, VIN must remain between 2.7V and 5.5V, with minimum VIN determined by VOUT + VDO (≥2.65V for 2.5V output).

Does the TPS79425DGNRG4 require an external noise-reduction capacitor?

No - the TPS79425DGNRG4 is a new-chip revision with NR/NC pin not internally connected. It delivers 71µVRMS output noise (100Hz–100kHz) without external CNR. Adding capacitance to Pin 4 provides no noise benefit and may impair thermal performance if not grounded properly.

Can the TPS79425DGNRG4 be used with a 1µF output capacitor?

No - the TPS79425DGNRG4 requires a minimum 2.2µF ceramic output capacitor (X5R/X7R) for stability. Using 1µF risks oscillation and degraded transient response. The datasheet explicitly states 2.2µF as the minimum effective value for new-chip devices; lower values are only permitted with feed-forward capacitors in legacy variants.

What is the purpose of the exposed thermal pad (Pin 5) on the TPS79425DGNRG4 HVSSOP-8 package?

The exposed thermal pad (Pin 5, GND) is electrically and thermally connected to the die substrate. It must be soldered to a dedicated PCB copper pour tied to system ground to achieve the specified R_θJB = 25.3°C/W and prevent thermal shutdown under 250mA load. Omitting thermal pad connection degrades power handling by >40%.

How does the active discharge feature operate in the TPS79425DGNRG4?

When the EN pin is driven low, the TPS79425DGNRG4 activates an internal pulldown MOSFET between OUT and GND, discharging the output capacitor rapidly. This prevents residual voltage from holding downstream logic in undefined states. Discharge time depends on C_OUT size but typically falls below 100µs for ≤10µF capacitors.