The HFDA80D and HFDA90D feature a 7mm x 7mm miniature package, simplifying design and reducing BOM costs
June 24, 2025, China — STMicroelectronics has introduced automotive-grade Class D audio amplifiers for smart cockpit applications. The devices have a compact overall size and are equipped with digital input interfaces, simplifying circuit design.

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The new HFDA80D and HFDA90D are the latest additions to STMicroelectronics' high-frequency automotive audio amplifier product family, complementing the existing analog input automotive-grade audio amplifier HFA80A. All products in the series operate at a switching frequency of 2MHz, saving PCB board space and reducing bill of materials (BOM) costs. These chips also feature an innovative architecture that minimizes the number of package pins and external components, using a 7mm x 7mm LQFP48 package with a heat sink on top of the chip and four channels of 27W output.
The HFDA80D and HFDA90D are equipped with digital input interfaces, further simplifying system integration and circuit design by eliminating the need for an analog-to-digital converter, thereby freeing up more space. The new products enhance audio clarity and offer higher energy efficiency compared to similar devices on the market.
Both the HFDA80D and HFDA90D feature an I2C bus interface for convenient user configuration and control, providing high output power for in-vehicle infotainment audio applications. The new products have minimal audio processing latency, making them suitable for active noise cancellation (ANC) and road noise cancellation (RNC) systems.
These amplifiers are specifically designed to address the challenges of automotive electrical environments, effectively suppressing POP noise and noise caused by battery voltage fluctuations and switching transients. Spread-spectrum functionality ensures the amplifiers inherently comply with the CISPR25 Class V standard. Additionally, the new product features comprehensive diagnostic functions, including open-circuit detection during playback, overcurrent protection, protection against Vcc short circuits or ground short circuits during startup, output diagnostics, and overheat alerts. The HFDA90D incorporates built-in load admittance measurement (DAM) and real-time load current monitoring, enabling designers to freely configure diagnostic functions and ensure exceptional linearity of the speakers.