DESCRIPTION

· The CMX148 is a half-duplex audio, signalling, and data processing IC designed for leisure and professional PMR systems, supporting CTCSS/DCS encoding/decoding.

· It offers comprehensive audio processing, including filtering, companding, pre/de-emphasis, and frequency inversion scrambling.

· Features an FFSK/MSK data modem for packetised or free-format data operations.

FEATURES

· Concurrent audio, signalling, and data operations.

· Complete audio-band processing with selectable options for filtering, companding, and highpass filter cut-off.

· Programmable voice scrambler and MSK/FFSK data modem with FEC, CRC, interleaving, and scrambling.

· DTMF and audio tone encoder/decoder, sub-audio signalling filters for CTCSS and DCS.

· Dual auxiliary ADC with four multiplexed inputs, four auxiliary DACs, and dual programmable system-clock outputs.

· Tx outputs for single, two-point, or I/Q modulation, microphone and discriminator analogue inputs, digital gain adjustments, and C-BUS serial interface to host µC.

· Flexible powersave modes and signal routing for host µC based encoding/decoding.

APPLICATIONS

· Professional PMR systems.

· Leisure radio systems including PMR, FRS, MURS, PMR446, and GMRS.