At present, there are two main schemes for high volume in the market: one is to use 5V boost to power class D power amplifier to obtain high volume, such as 5V boost to power aw8145; The second is the class-k power amplifier with built-in boost. For example, aw8736. This paper mainly introduces the differences between the two.
Aiming at the application scheme of using 5V boost to supply power to aw8145 to obtain high volume, based on the consideration of performance optimization and scheme robustness, it is suggested to connect a Schottky diode to ground reversely at two output terminals of power amplifier to reduce the influence of dead time freewheeling current. This design scheme is only for your reference.
Application 1: 5V boost plus aw8145 application design
For the high-volume solution, Ai Wei has launched a single-chip solution: the sixth generation class-k music amplifier aw8736, with built-in boost circuit, which can save the external materials and reduce the layout space for customers.
Aw8736 is the sixth generation of class k music amplifier with high efficiency, ultra-low distortion and constant high volume, which is specially developed to improve the sound quality of smart phones. Using the new generation of charge pump boost technology k-chargepump architecture, the efficiency is up to 92%, the overall efficiency of power amplifier is up to 75%, greatly extending the use time of intelligent machine; 0.02% ultra-low distortion and unique anti broken technology bring high-quality music enjoyment. The output power will not drop with the decrease of lithium battery voltage. The output power remains constant in the whole working voltage (3.3v-4.35v) of the mobile phone. Aw8736 adopts a slim 2mm & times; 2mm FC-16 package.
Application 2: aw8736