The MSM7508B and MSM7509B are single-channel CODEC CMOS ICs for voice signals ranging from 300 to 3400 Hz. These devices contain filters for A/D and D/A conversion. Designed especially for a single-power supply and low-power applications, these devices are optimized for telephone terminals in ISDN and digital wireless systems. The MSM7508B/MSM7509B are the transmission-clocks extended versions of the MSM7508/ MSM7509. It is recommended to use the MSM7508/MSM7509 for the transmission clocks of 64, 128, 256kHz.