MT9125

The Dual-channel ADPCM transcoder MT9125 is a low power, CMOS device capable of two encoder functions and two decoder functions. Two 64 kbit/s PCM channels are compressed into two 32 kbit/s ADPCM channels, and two 32 kbit/s ADPCM channels are expanded into two 64 kbit/s PCM channels. The 32 kbit/s ADPCM transcoding algorithm utilized conforms to CCITT Recommendation G.721 and ANSI T1.303-1989. The MT9125 also supports a 24 kbit/s (three bit word) algorithm (CCITT/G.723). Switching, on-the-fly, between 32 kbit/s and 24 kbit/s, is possible by toggling the appropriate Mode Select (MS1-MS4) control pins.