AW87318

IV sensing is a technology that continuously monitors both the current (I) and voltage (V) at the speaker output to estimate speaker temperature and excursion in real-time. The AW87318 uses this information to implement advanced speaker protection algorithms. By measuring the electrical impedance of the speaker, the amplifier can detect when the voice coil is approaching dangerous temperatures or when the diaphragm is exceeding safe excursion limits. When these limits are approached, the amplifier automatically reduces gain or applies compression to protect the speaker while maintaining audio output. This real-time protection is superior to traditional thermal sensors because it responds much faster and can predict thermal issues before they occur. IV sensing also enables speaker characterization, allowing the amplifier to optimize its performance for specific speaker models.

IV sensing provides superior speaker protection for high-power applications. Essential for small speakers in smartphones.

The AW87318 DSP features are configured through the I2C control interface. Awinic provides a comprehensive software driver and configuration tools that simplify the setup process. Key DSP features include: Dynamic Range Compression (DRC) which maintains consistent loudness across different content. Psychoacoustic Bass Boost which enhances perceived bass without increasing physical excursion. Equalization filters for customizing the frequency response. The configuration process involves: Initializing the I2C interface and verifying communication. Loading a preset configuration or custom parameters based on your speaker characteristics. Enabling the desired DSP features through control registers. Fine-tuning parameters during acoustic testing to optimize sound quality. Awinic provides reference configurations for common speaker types, and our FAE team can assist with custom tuning for your specific acoustic system.

Use Awinic provided software tools for DSP configuration. Contact our FAE team for acoustic tuning support.

The adaptive boost converter integrated in the AW87318 maintains a consistent output supply voltage for the Class-D amplifier stage, independent of the battery voltage. This is important because lithium battery voltage varies from 4.2V when fully charged to around 3.3V when nearly depleted. Without a boost converter, output power would decrease significantly as the battery discharges. The adaptive boost automatically adjusts its output voltage based on the audio signal level - it provides higher voltage only when needed for peak output, improving efficiency during normal listening levels. The boost converter can provide up to 8.5V output, enabling the 5W output power capability. This adaptive behavior optimizes battery life while maintaining consistent audio performance throughout the battery discharge cycle. The boost converter uses synchronous rectification for high efficiency and includes protection features for reliable operation.

Adaptive boost maintains consistent audio performance across battery voltage range. Essential for high-power applications.

Optimizing PCB layout for the AW87318 is critical for achieving maximum performance and minimizing EMI. Key layout guidelines include: Place the AW87318 close to the speaker connector to minimize output trace length and radiation. Use wide, short traces for the speaker output connections to minimize resistance and inductance. Implement a solid ground plane under the device with multiple vias to the main ground plane for low impedance. Place decoupling capacitors as close as possible to the supply pins, using a combination of 10uF and 0.1uF capacitors. Keep digital control lines (I2C) away from analog audio paths to prevent noise coupling. Use differential routing for the speaker outputs when possible to reduce common-mode radiation. The exposed pad on the bottom of the package should be connected to ground with multiple vias for thermal dissipation. Awinic provides reference layouts and can review customer designs for optimization.

Follow Awinic layout guidelines for optimal performance. Contact our FAE team for layout review.

The AW87318 is optimized for micro speakers commonly used in smartphones and portable devices. These speakers typically have diameters of 10-20mm, impedances of 4-8 ohms, and power handling of 0.5-1W continuous. The Smart PA technology is particularly beneficial for these small speakers because: The high output voltage swing (up to 8.5V) enables higher SPL from low-impedance speakers. The real-time protection prevents damage to the delicate speaker suspensions. The DSP enhancement can compensate for the limited bass response of small speakers. When selecting a speaker, consider: Impedance - 4-ohm speakers will deliver higher SPL but require more current. 8-ohm speakers are easier to drive but produce lower output. Power handling - ensure the speaker can handle the peak power delivered by the amplifier. Frequency response - speakers with extended high-frequency response will benefit more from the DSP bass boost. Awinic can provide speaker characterization services to optimize the amplifier configuration.

AW87318 works best with 4-8 ohm micro speakers. Contact our FAE team for speaker selection guidance.

The AW87318 offers competitive advantages compared to other Smart PA solutions in the market: The integrated IV sensing provides more accurate speaker protection than temperature-sensor-based approaches used by some competitors. The DSP integration enables advanced audio features without requiring external DSP chips, reducing BOM cost. The efficiency is industry-leading, with >90% efficiency at typical operating points, comparable to or better than competing solutions. The package size is among the smallest available, enabling compact smartphone designs. Awinic's local support in China provides faster response times for customers in the Asian market. The cost-effectiveness is a key advantage - AW87318 delivers flagship performance at a more competitive price point than premium competitors. For customers seeking a balance of performance, features, and cost, the AW87318 is an excellent choice. Awinic continues to invest in R&D to maintain competitive leadership in the audio amplifier market.

AW87318 offers excellent performance-to-cost ratio. Contact our FAE team for competitive analysis.