STMicroelectronics TDA7268

Overview

TDA7268 from STMicroelectronics is a dual-channel 2W stereo audio amplifier in PowerDIP-16 package, designed for TV audio output stages with rail-to-rail complementary output stage, fixed 32dB gain, and 4.5–18V wide supply range. Delivers 2W per channel into 8Ω at 10% THD with 12V supply, features thermal protection, AC short-circuit protection, and standby mode drawing <300µA.

For engineers reviewing the TDA7268 datasheet, TDA7268 pinout, TDA7268 application, or TDA7268 equivalent, key selection criteria include its no-bootstrap-output architecture, SVR capacitor for ripple rejection, low pop noise during turn-on/off, minimal external components (no feedback cap or Boucherot cell), and DC-coupled input compatibility with TV system signal chains.

Technical Context

The TDA7268 integrates fully complementary Class-AB output stages eliminating bootstrap capacitors and enabling true rail-to-rail voltage swing. Its internal fixed 32dB gain and 50–100kΩ input impedance simplify front-end interfacing without external gain-setting resistors.

It employs dual independent ground paths (S-GND and P-GND), dedicated SVR pin for supply ripple filtering, and logic-controlled standby via Pin 3 with 1V enable threshold and >60dB attenuation. Thermal shutdown activates at 150°C junction temperature, with R_{th j-amb} = 70°C/W on PCB.

Key Specifications

Pinout & Package

Package: PowerDIP-16 (16-pin dual-in-line with extended heat-dissipating tab), 20.0mm × 8.8mm body, 2.54mm pitch, RoHS-compliant lead finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TDA7268, TDA7265 offers higher power but demands more board space and external compensation, while LM4863 suits battery systems but lacks SVR filtering and wide-supply resilience - making TDA7268 uniquely optimized for cost-sensitive, ripple-prone TV audio stages.

Availability

TDA7268 is available at Aetrix Electronics and suitable for compact TV audio output, set-top box speaker drivers, portable DVD player amplifiers, and soundbar channel drivers requiring stable component supply across long-lifecycle consumer electronics programs.

Supply support for TDA7268 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, designing and manufacturing analog, microcontroller, power, and sensor solutions for automotive, industrial, and consumer markets.

The TDA7268 belongs to ST's TV audio amplifier product line, engineered specifically for cost-effective, high-reliability stereo output stages in CRT, LCD, and early flat-panel television platforms with SMPS-derived supplies.

FAQ

What is the minimum supply voltage for reliable operation of the TDA7268?

The TDA7268 operates reliably down to 4.5V per channel, verified across temperature (0–70°C) and load (4–16Ω). Below this, output clipping occurs earlier and thermal regulation may activate prematurely due to reduced headroom. It is not specified for 3.3V or 5V-only systems.

Can the TDA7268 drive 4Ω speakers, and what derating applies?

Yes - it delivers 1.8W per channel into 4Ω at 9V supply (THD = 10%). At 12V, continuous 4Ω operation requires external heatsinking to maintain R_{th j-amb} ≤40°C/W, as power dissipation rises ~35% versus 8Ω loads. Derating curves in Figure 3 of the datasheet confirm safe operation up to 70°C ambient with proper copper area.

Is the SVR pin mandatory, and what capacitor value is recommended?

SVR is optional but strongly recommended: a 100µF low-ESR electrolytic capacitor between SVR and S-GND improves supply ripple rejection by up to 50dB at 1kHz. Without it, measured SVR drops to ~40dB, increasing audible hum in SMPS-based TV designs. Ceramic bypass (0.1µF) should also be placed near VS pins.

Does the TDA7268 require a Boucherot cell or Zobel network at the output?

No - the TDA7268's internal compensation and stable phase margin eliminate the need for external Zobel networks or Boucherot cells. Its output stage remains unconditionally stable driving reactive speaker loads (including 8Ω nominal with 4–20Ω impedance sweeps) without oscillation or ringing.