STM32手册里一直有一种封装，但是我很少用，就是这种WLCSP封装。 可以简单对比一下。同样是48或者49脚，QFN封装的尺寸是7x7mm，而WLCSP只有3x3.2mm。

A good audio codec for live applications such as telecommunication is characterized by three key properties: (1) compression, i.e. the bitrate that is required to ...