They are nearly identical, both offering a digital (I2S) front-end, a digital core, a 24-bit DAC (100dB resolution), a class-D transimpedance PWM output stage, and internal feedback before the necessary external LC output filter.
"Thank you for interpolation and noise shaping, digital signal processing makes it possible to achieve good sound performance in a small device area,” said ST. "The internal PLL uses the bitstream clock to generate the internal clock for the digital part and the PWM for the outputs."
You can select a sampling frequency from 8 to 96 kHz. , where lower frequencies consume less memory when storing warning tones.
Source: electronicsweekly.com
