MSM9552 Datasheet, PDF (1/7 Pages) OKI electronic componets – LSI for FM Multiplex Data Demodulation

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MSM9552/MSM9553
LSI for FM Multiplex Data Demodulation
MSM9552/MSM9553
GENERAL DESCRIPTION
The MSM9552 and MSM9553 are LSI devices which demodulate FM character multiplex signals in
the DARC (DAta Radio Channel)* format to acquire digital data. The MSM9552 and MSM9553
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 MSM9552 and MSM9553 has a bandpass filter consisting of SCF, frame synchroniza-
tion circuit, error correction circuit, etc. 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 MSM9552 and MSM9553 have a simple configuration, and are equipped with only necessary
functions. By making changes to software for the external microcontroller, the MSM9552 and
MSM9553 can meet the various requirements of FM multiplex broadcasting services which will be
offered in future.
These LSI devices are best suited to the radio sets and information devices for FM character multiplex
broadcasting, which started in Japan in October 1994. Especially, the MSM9553 is suitable for
portable units.
* 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.
FEATURES
• Built-in bandpass filter (SCF)
• Built-in block synchronization circuit and frame synchronization circuit
• Setting of the number of synchronization protecting stages
• Regeneration of data clocks by digital PLL
• 1T delay detection
• Built-in error correction circuit
• Built-in layer 4 and layer 2 CRC check circuit
• Microcontroller parallel interface
• Clock output for external devices (64kHz to 8.192MHz selectable)
• International standard frame format
• Power source: 5V (MSM9552), 3V (MSM9553)
• Package
44-pin plastic QFP (QFP44-P-910-0.80-2K)
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