when is pdm used
PCM (Pulse Code Modulation): a system for representing a sampled signal as a series of multi-bit words. This is the technology used in audio CDs. PDM (Pulse Density Modulation): a system for representing a sampled signal as a stream of single bits. Sampling rate is the rate at which a signal is sampled to produce a discrete-time representation. Wordlength is the number of bits used to represent a sample.