STMicroelectronics TDA7266S

Overview

TDA7266S from STMicroelectronics is a dual-channel Class-AB bridge-tied-load (BTL) audio power amplifier IC designed for TV and portable radio systems. It delivers 5W per channel into 8Ω at 11V supply, operates from 3–18V, features internally fixed 26dB gain, and integrates standby/mute control, thermal shutdown, and short-circuit protection - enabling compact, low-BOM audio output stages in space-constrained consumer electronics.

For engineers reviewing the TDA7266S datasheet, TDA7266S pinout, TDA7266S application, or TDA7266S equivalent, key selection criteria include its wide supply range (3–18V), absence of bootstrap/Boocherot capacitors, dual BTL architecture with independent mute/standby inputs, and thermal protection threshold at 150°C - all critical for robust, low-component-count stereo audio amplification in cost-sensitive embedded audio designs.

Technical Context

The TDA7266S implements a dual BTL output stage with fully integrated biasing and protection logic, eliminating external bootstrap networks and SWR compensation capacitors. Its internal voltage reference (Vref) stabilizes quiescent current across supply variations, while separate ST-BY and MUTE pins enable precise sequencing to suppress turn-on/turn-off pop-noise.

It uses BiCMOS BI20II process technology and features matched closed-loop gain (±0.5dB matching between channels), 46–60dB crosstalk suppression, and 40–56dB supply voltage rejection - confirming suitability for mixed-signal environments where power rail noise and inter-channel isolation are design constraints.

Key Specifications

Pinout & Package

Package: Multiwatt-15 (vertical, 15-pin, thermally enhanced SIP with integral heat slug). Pin 1–15 arranged in single row; mounting hole centered at L3/L4; case temperature monitored via exposed backplate.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TDA7265 and TPA2013D1, the TDA7266S uniquely combines BTL architecture, zero-external-bootstrap operation, and analog-mappable ST-BY/MUTE thresholds - making it optimal for cost-sensitive, low-noise, pop-free analog audio stages where layout simplicity and supply flexibility outweigh raw efficiency or maximum power.

Availability

TDA7266S is available at Aetrix Electronics and suitable for TV audio output stages, portable radio amplifiers, set-top box interfaces, and compact home audio docks requiring stable component supply and long-term production continuity.

Supply support for TDA7266S 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 automotive, industrial, and consumer ICs with strong analog and power portfolio heritage.

The TDA7266S belongs to ST's legacy audio power amplifier product line, engineered specifically for cost-optimized, low-BOM-count stereo audio output in mainstream consumer electronics - emphasizing ease of use, thermal robustness, and pop-noise immunity.

FAQ

What is the minimum supply voltage for reliable operation of the TDA7266S?

The TDA7266S operates reliably down to 3V DC supply, delivering usable output power (≥1W per channel) into 8Ω loads at this voltage. Quiescent current remains stable across the full 3–18V range, and internal protection circuits remain functional - confirmed by Figure 8 (Iq vs. Vsupply) and Absolute Maximum Ratings table.

How does the ST-BY pin function, and what voltage level activates it?

The ST-BY pin is active-high with a threshold of 0.8–1.8V (typ. 1.3V). When voltage at pin 7 exceeds this range, the amplifier powers up its bias circuitry; below threshold, it enters ultra-low-current standby (100µA). An external RC network controls ramp rate to prevent pop-noise - detailed in Figure 1 and Application Suggestion section.

Can the TDA7266S drive 4Ω speakers, and what derating applies?

Yes - the TDA7266S can drive 4Ω loads, but output power increases to ~7W per channel at 11V, raising junction temperature. Derating is required: maximum continuous power drops to 3.5W per channel at 4Ω to maintain safe thermal margin below 150°C, per thermal data (Rth j-case = 1.6–2.2°C/W) and SOA curves in datasheet pages 6–7.

Is there a recommended PCB layout for minimizing thermal resistance?

Yes - the Multiwatt-15 package requires direct copper pour connection to the exposed backplate (pins 3, 8, 9 ground planes tied to large thermal pad), with ≥4 thermal vias (0.3mm diameter) under the slug connecting to inner-layer ground planes. Layout Fig. 3b shows optimized copper area and decoupling placement - critical to achieve specified Rth j-case ≤2.2°C/W.