Ic For Fm Multiplex Data Demodulation

The MSM9560 is an IC which demodulates FM character multiplex signals in the DARC (Data Radio Channel)*1 format to obtain digital data. The MSM9560 operates at 4.5 to 5.5 V. In the DARC system, 16 kbps of digital data L-MSK modulated at 76 kHz is multiplexed on an ordinary FM broadcast base band signal. The MSM9560 contains on one chip a band pass Filter using a switched capacitor Filter (SCF) and a group of circuits including a frame synchronization circuit and an error correction circuit. By connecting an external FM receiver and memory for temporary data storage and by controlling them by the CPU, a system for obtaining digital data CAN easily be constructed. The FM multiplex demodulation ICs, the MSM9500-series devices, are configured with minimum functions; so they will, merely by making changes to the software of the external microcomputer, be able to respond flexibly to the many FM multiplex broadcast services that are going to come about in the future. By Oki Semiconductor