idt high definition audio codec
AC'97 (short for Audio Codec '97; also MC'97, short for Modem Codec '97) is Intel Corporation's Audio "Codec" standard developed by the Intel Architecture Labs in 1997, and used mainly in motherboards, modems, and sound cards.
Intel's use of the word audio codec refers to signals being encoded/decoded to/from analog audio from/to digital audio, thus actually a combined audio AD/DA-converter. This should not be confused with a codec in the sense of converting from one binary format to another, such as an audio (MP3) or video (Xvid) codec in a media player.
Audio components integrated into chipsets consists of two components: an AC'97 digital controller (DC97), which is built into the I/O Controller Hub (ICH) of the chipset, and an AC'97 audio and modem codecs, which is the analog component of the architecture. AC'97 defines a high-quality, 16- or 20-bit audio architecture with surround sound support for the PC that is used in the majority of today's desktop platforms. AC'97 supports 96,000 samples/second in 20-bit stereo resolution and 48,000 samples/second in 20-bit stereo for multichannel recording and playback.
Integrated audio is implemented with the AC'97 Codec on the motherboard, a Communications and Networking Riser (CNR) card, or an audio/modem riser (AMR) card.
AC '97 v2.3[1] enables Plug and Play audio for the end user. This version provides parametric data about the analog device being used.
In 2004 AC'97 was superseded by Intel High Definition Audio (HD Audio).