The STMicroelectronics TDA7901 automotive amplifier integrates a buck controller for Class G power switching and supports High Definition Audio – a unique combination on the market for optimal listening and high efficiency.
In class G operation, the TDA7901 buck controller automatically optimizes the voltage supplied to the bridge-tied load (BTL) power stage depending on the audio signal level. The resulting smooth analog sound comes with near class D efficiency at normal listening levels.
Furthermore, as the power dissipation is much lower compared to a conventional class A/B amplifier, the heat sink requirements are optimized. The integration of the Buck controller into the IC contributes to reducing the size and weight of the system. It also reduces the bill of materials, simplifies circuit design, and saves developing firmware to control the voltage bus.
The TDA7901 is suitable for use in many in-vehicle information (IVI) systems such as head units, smart cabin systems, external amplifiers and more. The amplifier signals full diagnostics in operation, including real-time load current monitoring via I2S or I2C interfaces, enabling ASIL-A certification of safety-related applications such as warning tone generators and acoustic vehicle warning systems (AVAS).
A digital impedance meter is also provided, ensuring that systems containing the TDA7901 can meet the most demanding requirements of automotive OEMs.
With its I2S digital input and smart quad-BTL output, the TDA7901 delivers 4x 43W of audio power (with 4Ω load, saturated output at 14.4V). The amplifier has 80kHz bandwidth to handle high definition audio. Its wide supply voltage range, ranging from 4.5V to 18.5V, prevents interruptions caused by start-stop engine operation and general automotive electrical transients.
