Texas Instruments TPA301DGH

Overview

TPA301DGH from Texas Instruments is a 350-mW bridge-tied load (BTL) mono audio power amplifier optimized for low-voltage portable applications. It delivers 250 mW into 8 Ω at 3.3 V and 350 mW at 5 V with ≤1% THD+N, features 0.15 µA shutdown current, thermal/short-circuit protection, and operates from 2.5 V to 5.5 V supply. It targets internal speaker drive in cellular handsets and compact audio systems.

For engineers reviewing the TPA301DGH datasheet, TPA301DGH pinout, TPA301DGH application, or TPA301DGH equivalent, this page provides verified specifications, SOIC-8 package mapping, BTL output architecture details, thermal derating data, and real-world substitution guidance for battery-powered audio designs requiring capacitor-free speaker coupling.

Technical Context

The TPA301DGH implements a dual-rail CMOS BTL output stage that eliminates external DC-blocking capacitors by generating complementary VO+ and VO− signals referenced to mid-supply (VDD/2). Its internal bias network uses the BYPASS pin to stabilize the virtual ground at VDD/2 via a 0.1–1 µF capacitor, enabling rail-to-rail signal swing without output offset.

It integrates a shutdown control input (SHUTDOWN pin) that reduces quiescent current to 0.15 µA when driven high, and features built-in thermal foldback and short-circuit current limiting. The device's unity-gain bandwidth is 1.4 MHz, supporting stable operation with gain-setting resistors (RI/RF) and optional 5-pF compensation for RF > 50 kΩ.

Key Specifications

Pinout & Package

TPA301DGH is housed in an 8-pin SOIC (D) package with standard 1.27-mm pitch, RoHS-compliant NiPdAu lead finish, and MSL Level-1 rating. The package supports surface-mount reflow and provides thermal dissipation of 725 mW at TA = 25°C (derated to 377 mW at 85°C).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar mono BTL audio amplifier applications.

Compared with TPA301DGH, TPA3110D2 offers significantly higher power and efficiency but demands more board space and higher minimum voltage, while MAX9718 matches voltage and output specs but adds design complexity with external bias components - making TPA301DGH optimal for compact, low-component-count 3.3-V portable audio.

Availability

TPA301DGH is available at Aetrix Electronics and suitable for cellular handset audio, portable media player speaker drive, smart wearable voice prompts, and IoT edge device alert tone generation requiring stable component supply and long-term production continuity.

Supply support for TPA301DGH 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 over 50 years of innovation in power management and signal chain solutions.

The TPA301DGH belongs to TI's low-voltage audio amplifier product line, designed specifically for space- and power-constrained portable electronics where capacitor-free BTL speaker drive, ultra-low shutdown current, and voice-band fidelity are essential.

FAQ

What is the maximum continuous output power of the TPA301DGH into an 8-Ω load?

The TPA301DGH delivers 350 mW continuous output power into an 8-Ω load at 5 V supply with ≤2% THD+N, and 250 mW at 3.3 V with ≤1.3% THD+N. These values are measured under BTL configuration with specified test conditions per the official TI datasheet SLOS208E. Output power scales with supply voltage squared, so operation at 4.2 V (typical Li-ion) yields ~290 mW.

Does the TPA301DGH require external DC-blocking capacitors on its outputs?

No, the TPA301DGH does not require external DC-blocking capacitors because it uses a bridge-tied load (BTL) architecture with complementary VO+ and VO− outputs. This configuration cancels DC offset across the speaker, eliminating the need for large electrolytic coupling capacitors - a key advantage for miniaturized portable designs.

What is the function of the BYPASS pin on the TPA301DGH?

On the TPA301DGH, the BYPASS pin provides access to the internal VDD/2 mid-supply reference used for input biasing and output stage symmetry. It must be connected to a 0.1–1 µF low-ESR capacitor to stabilize the virtual ground, reduce startup pop, and maintain PSRR and THD+N performance - failure to do so causes distortion and instability.

Can the TPA301DGH operate from a single 3.0-V lithium-ion battery?

Yes, the TPA301DGH operates from 2.5 V to 5.5 V, fully covering the discharge curve of a single Li-ion cell (3.0–4.2 V). At 3.0 V, it delivers ~200 mW into 8 Ω with acceptable THD+N for voice applications. Its wide supply range eliminates the need for voltage regulation in battery-powered portable audio systems.

How does the shutdown feature of the TPA301DGH reduce system power consumption?

The TPA301DGH shutdown feature reduces total supply current to just 0.15 µA when the SHUTDOWN pin is driven high (≥0.9×VDD), cutting quiescent power to negligible levels. This allows integration into always-on systems like smart wearables, where audio is activated only on demand - extending battery life by weeks in intermittent-use scenarios.