STMicroelectronics TDA7266D

Overview

TDA7266D from STMicroelectronics is a dual-channel bridge-tied-load (BTL) audio power amplifier IC designed for compact stereo audio output stages in LCD TV, PC motherboard, and portable audio systems. It delivers 5W + 5W into 8Ω loads at 9.5V supply with 10% THD, operates from 3.5–12V single supply, features internally fixed 26dB gain, and integrates stand-by/mute control with thermal and short-circuit protection.

For engineers reviewing the TDA7266D datasheet, TDA7266D pinout, TDA7266D application, or TDA7266D equivalent, key selection considerations include its PowerSO-20 Slug Down package thermal performance, absence of external bootstrap/SVR capacitors, mute threshold voltage dependency on VCC, and dual-BTL channel matching (∆GV ≤ 0.5dB) for balanced stereo output.

Technical Context

The TDA7266D uses bipolar Bi20II process technology to implement two fully independent BTL amplifier channels with shared thermal shutdown and overcurrent protection circuitry. Each channel accepts differential-capacitor-coupled inputs and drives low-impedance speakers directly without output inductors or Zobel networks.

Its internal fixed-gain architecture eliminates external feedback resistors, while the integrated mute/st-by logic requires precise voltage sequencing (stand-by first, then mute release after 100–200ms) to suppress turn-on/turn-off pop noise. Thermal protection triggers at 150°C junction temperature, with R_{th j-amb} = 15°C/W achievable on FR4 PCBs with 15 via holes and ground plane.

Key Specifications

Pinout & Package

Package: PowerSO-20 Slug Down (JEDEC MO-166), thermally enhanced with exposed copper slug soldered to PCB ground plane for direct heat transfer. Requires ≥15 thermal vias under slug and dedicated 3×3 cm copper pour for R_{th j-amb} = 15°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TDA7265 and TPA3110D2, the TDA7266D offers lowest BOM count and simplest layout for 5W-class applications, trading peak power and efficiency for integration and ease of qualification in cost-sensitive consumer displays.

Availability

TDA7266D is available at Aetrix Electronics and suitable for LCD TV audio subsystems, PC motherboard integrated amplifiers, and portable media player designs requiring stable component supply, long-lifecycle availability, and production-ready thermal validation.

Supply support for TDA7266D 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, specializing in analog, power, microcontrollers, and automotive ICs with vertical manufacturing and broad distribution.

The TDA7266D belongs to ST's legacy audio power amplifier product line, engineered specifically for cost-sensitive, space-constrained consumer audio applications where simplicity, thermal robustness, and rapid time-to-market are critical.

FAQ

What is the minimum recommended PCB copper area and via count for thermal management?

The datasheet specifies a 3×3 cm ground copper pour with 15 thermal vias (0.3mm diameter) under the PowerSO-20 slug to achieve R_{th j-amb} = 15°C/W. Using fewer vias or smaller copper area increases junction temperature and may trigger thermal shutdown at lower output power levels, especially above 9V supply.

How should ST-BY and MUTE signals be sequenced to avoid pop noise?

At power-on: assert ST-BY high first, wait 100–200ms for internal biasing to stabilize, then de-assert MUTE. At power-off: assert MUTE first, then de-assert ST-BY. This sequence prevents large DC transients at the outputs by ensuring amplifier stages are disabled before input coupling capacitors discharge.

Can the TDA7266D drive 4Ω speakers?

Yes, but with reduced maximum supply voltage: the datasheet specifies 6.5V max for 4Ω loads to limit dissipated power to 5W and avoid thermal shutdown. At 9.5V/4Ω, output power exceeds safe thermal limits even at moderate THD, risking automatic shutdown during sustained playback.

Is there an evaluation board available, and what does it demonstrate?

Yes - ST provides the STEVAL-CCA003V1 evaluation board, which implements the reference dual-BTL application circuit with proper GND separation, thermal vias, and ceramic decoupling placement. It validates full 5W+5W output, THD performance, and mute/standby timing behavior per the datasheet test conditions.