Overview

The LC72711W and LC72711LW are data demodulator ICs for receiving FM multiplex broadcasts for mobile reception in the DARC format. This IC includes an onchip bandpass filter for extracting the DARC signal from the FM baseband signal. Furthermore, since this IC supports all of the IT-R recommended FM multiplex frame structures (methods A, A’, B, and C), it is optimal for worldwide market radios that provide FM multiplex reception. The LC72711W and LC72711LW support both parallel and CCB serial CPU interfaces.

Functions

• Adjustment-free 76kHz SCF bandpass filter

• Supports all FM multiplex frame structures (methods A, A’, B, and C) under CPU control.

• MSK delay detection system based on a 1T delay.

• Error correction function based on a 2T delay (in the MSK detection stage)

• Digital PLL based clock regeneration function

• Shift-register 1T and 2T delay circuits

• Block and frame synchronization detection circuits

• Functions for setting the number of allowable BIC errors and the number of synchronization protection operations.

• Error correction using (272, 190) codes

• Built-in layer 4 CRC code checking circuit

• On-chip frame memory and memory control circuit for vertical correction

• 7.2MHz crystal oscillator circuit

• Two power saving modes: STNBY and EC STOP

• Applications can use either a parallel CPU interface (DMA) or a CCB serial interface.

• Supply voltage: 4.5 to 5.5V (LC72711W), 2.7 to 3.6V (LC72711LW)