ST HFDA801A with integrated LC low-pass filter
2MHz switchable PWM class D amplifier
Widely applicable to HD and safety audio battlefields, etc.


STMicroelectronics released the 'HFDA801A' high-resolution audio amplifier for small battlefields on the 10th.

The HFDA801A is a 2MHz switching PWM (Pulse-Width Modulation) Class D amplifier in a quad-bridge configuration. The integrated high-performance DAC (Digital-to-Analog Converter) supports noiseless turn-on/off under all load conditions, and ensures Hi-Fi sound quality without generating output artifacts.

With a signal-to-noise ratio (SNR) of 121 dB, a dynamic range of 120 dB, and output noise of 10 μV, it provides a high level of audio performance even in an inexpensive, small form factor. The feedback configuration incorporates an LC low-pass filter, providing a flat response characteristic up to 80 kHz and reducing the use of external components.

It supports wide bandwidth and can be used in high-definition audio applications, allowing designers to achieve excellent linearity and low distortion without being concerned about the quality of inductors and capacitors.

The HFDA801A’s unique architecture derives all of the voltages required internally, allowing it to be powered from the car battery without the use of an additional power converter. Its wide load capability allows all four channels to drive high output into 2Ω impedance loads while maintaining stable performance.

In addition to digital impedance measurement and real-time load current monitoring, it also integrates run-time diagnostic functions, making it suitable for use in safety-related audio applications that require ASIL compliance, such as Acoustic Vehicle Alerting Systems (AVAS).

The HFDA801A is currently sampling and is scheduled to be in production in the second half of 2021. Please contact your ST representative for pricing options and sample requests.