Class-D stereo audio amplifier sounds good for power saving
Claimed to save battery power while delivering superior sound quality, the PAM8965 Class-D stereo audio power amplifier by Diodes has an integrated synchronous boost converter.
The power amplifier is targeted for use in artificial intelligence (AI) -enabled speaker systems and portable musical instruments and any other applications where elevated output power, extended battery life and compact construction are key requirements.
The PAM8965 runs off a 2.8 to 8.5V supply and has the capability to drive 12W into 4Ohm speakers via each of its two channels, with 92 per cent efficiency. The incorporation of a synchronous boost converter, with pulse frequency modulation (PFM) operation at light loads, means the power amplifier is not only able to deliver augmented performance and efficiency levels, but it also reduces board space usage and lowers the overall bill of materials (BoM) costs, adds Diodes.
The product’s spread spectrum modulation (SSM) results in more effective EMI (electromagnetic interference) suppression across a range of frequencies, enabling the use of inexpensive ferrite bead filters, rather than more costly and bulky LC filters. The boost converter’s ultrasonic PFM operation minimises the impact of audible noise emanating from other components situated on the PCB. Class-D and boost SSM switching is synchronised to avoid beats.
The PAM8965’s non-clipping power limit ensures that speakers continue to provide superior audio fidelity without risk of damage, says Diodes. The thermal foldback function reduces output power if the amplifier device starts to overheat.
Under-voltage, over-voltage, and short-circuit protection, as well as thermal shutdown, are also included. A low quiescent current of just 10mA further conserves battery charge.
The PAM8965 is available in a 40-pin W-QFN package.
Diodes delivers semiconductor products to companies in the consumer electronics, computing, communications, industrial, and automotive markets. Its product portfolio includes discrete, analogue and mixed signal products, together with application-specific products and packaging technology.
The company has operations in 31 sites, including engineering, testing, manufacturing and customer service.