Diodes Incorporated introduces a 1.9W Class D audio amplifier

     Diodes Incorporated introduces the PAM8905, a 1.9W Class D audio amplifier for smartphones powered by single-cell lithium-ion batteries, suitable for audio systems that provide high voltage level horizontal output at low supply voltage. The new product generates the voltage rail of the output stage through the built-in boost converter, and at the same time, the battery tracking automatic gain control function is used to adjust the gain and limit the current of the battery in the case of low battery voltage, effectively extending the battery life.

     The PAM8905 features a high-efficiency Class D audio power amplifier and integrated boost converter that delivers up to 1.9W of power at just 1% total harmonic distortion plus noise (THD+N) to drive 8Ω speakers. The device's booster circuit is equipped with a comprehensive synchronous topology that reduces the number of external components, improves efficiency, and increases the amplifier's output power compared to a standard amplifier directly connected to the battery. The built-in automatic gain control ensures excellent sound quality and helps to further extend battery life.

     The PAM8905 features DC input voltage protection to prevent speaker damage when the input voltage is at a high DC bias level. The device also prevents output short circuits with fully automatic recovery and includes undervoltage latching and overtemperature protection. The PAM8905 is available in a 12-pin U-WLB1520-12 CSP package with dimensions of only 15mm x 20mm x 0.6mm, providing a low pin count and compact form factor solution to effectively reduce the board area.