The MC145480 is a general purpose per channel PCM Codec–Filter with pin
selectable Mu–Law or A–Law companding, and is offered in 20–pin DIP, SOG,
and SSOP packages. This device performs the voice digitization and
reconstruction as well as the band limiting and smoothing required for PCM
systems. This device is designed to operate in both synchronous and
asynchronous applications and contains an on–chip precision reference
voltage.