MSM9555

The MSM9554 and MSM9555 are LSI devices which demodulate FM character multiplex signals in the DARC (DAta Radio Channel)*¹ format to acquire digital data. The MSM9554 and MSM9555 operate on 5V and 3V, respectively. In the DARC format, baseband signals at ordinary FM broadcasting frequencies are multiplexed with 16k-bps digital data which are L-MSK-modulated at 76kHz.

Each of the MSM9554 and MSM9555 has a bandpass filter consisting of SCF, frame synchronization circuit, and error correction circuit, on a single chip.

So, a system for acquisition of digital data can be easily constructed by externally mounting an FM receiver tuner, microcontroller for control, and memory for temporary storage of data.

The MSM9554 and MSM9555 have a simple configuration, and are equipped with only necessary functions. By making changes to software for the external microcontroller, the MSM9554 and MSM9555 can meet the various requirements of FM multiplex broadcasting services which will be offered in future.

These MSM9555 are best suited to the car radios and car navigation systems supporting VICSs (Vehicle Information and Communication System)*² that have been serviced since Aprit, 1996.

*1 DARC is a registered trademark of NHK ENGINEERING SERVICES, INC.
  Note that a contract needs to be made with NHK Engineering Service if a manufacturer produces/sells electronic equipment utilizing the DARC technology.

*2 If samples or detail documents are to be provided, contracts with VICS center are reqired beforehand.