Developer of the first automotive class-D amplifier with digital input, ST supplies audio power amplifiers to the most important automotive audio makers for both premium sound systems and head units.

We offer a broad product portfolio covering all multi-channel requirements and continue to develop innovative solutions to always ensure the best sound quality combined with maximum energy efficiency and advanced features.

  • High amplification efficiency ratings
  • Robust automotive design with integrated protection against overstress conditions, such as short-circuits, electrostatic discharge (ESD), load dump, or over-temperature
  • A very advanced diagnostics processor
  • A proprietary feedback loop architecture, addressing the need for lower system cost and electromagnetic emissions
  • Fully digital processing
  • Ability to drive very low impedance speakers (as low as 1 ohm)
  • Compliance with stop/start and hybrid engine standards


New generation of class D amplifiers with amazing efficiency and load detection accuracy

We have launched the first members of our second generation of fully digital class-D amplifiers, which are already enjoying much success in car infotainment systems. With four powerful channels, our FDA801 and FDA801B class-D digital input power amplifiers help to drastically reduce system size and cost, bringing the concept of diagnostics to a next level.


Key features and main benefits:

Very high output power capability and class-D efficiency above 90-93%: Each output can deliver up to 50 W when the load is 4 ohms and the battery is 15.2 V. Power dissipation is strongly reduced, allowing car makers to meet their demands for class D solutions: high output power and maximum efficiency.

Digital impedance meter (DIM). The FDA801B is able to measure both load impedance and phase and deliver the highest load detection accuracy. Provided on the digital bus (I²C), this measurement function is used to detect misconnections and ensure precise diagnostics in the presence of any speaker or combination of them.

Low-pass output filter included in the feedback loop. This patented feature allows reducing the size of the filter components, where inductances down to 4.7µH can be used, leading to a very compact solution. It provides a flat frequency response, independent of the type of load and its variations, helping to ensure crystal-clear sound. It helps to meet the very stringent electromagnetic emission specifications without the use of complicated additional solutions.

I2S or TDM digital input. The digital input, immune to noise by construction, allows building sound systems with the highest audio quality without using expensive digital-to-analog converters.

I2C flexible diagnostics and full fault protection. Such thorough and complete diagnostics is unmatched in the automotive market. The device is able to detect any misconnection on any channel, in an independent manner, at any given time.

FDA802 and FDA802B further enlarge the new generation of ST’s family of automotive Class-D amplifiers with 2-channel amplifiers able to drive 8 ohm speakers up to 50V of supply voltage.