CMX885 CML Microcircuits Marine VHF Audio and Signalling Processor COMMUNICATION SEMICONDUCTORS D/885/4 June 2017 Audio and Signalling Processing, DTMF, DSC/ATIS and NOAA with Auxiliary Functions for use in Marine VHF Systems Features Concurrent Audio/Signalling/Data Operations Dual Auxiliary ADC, 4 Multiplexed Inputs Complete Audio-band Processing: 4 x Auxiliary DACs o Selectable Audio Processing Order Dual Programmable System Clock Outputs o Pre and De-emphasis Tx Outputs for Single, Two-Point Modulation o Selectable 2.55/3.0 kHz Filtering 3 x Analogue Inputs (Mic or Discriminator) o Limiter DSC/ATIS Modem for Marine Applications Digital Gain Adjustment Programmable Voice Scrambler Inband Signalling: DTMF, NOAA NWR C-BUS Serial Interface to Host Controller Default 3.6864MHz Xtal/Clock DTMF and Audio Tone Encoder/Decoder Flexible Powersave Modes Small VQFN and LQFP Packages Low-power 3.0V to 3.6V Operation Auxiliary Audio Out Multiplexed ADC Inputs Mic Input Auxiliary DACs IRQ Modulator CMX885 RF Host C C-BUS (Rx/Tx) Discriminator Marine VHF Baseband Processor Reference Clock nd Optional 2 Receiver 3V to 3.6V Supply RF Discriminator (Rx) System Clock 1 System Clock 2 Tx Enable Rx Enable 1 Brief Description The CMX885 is a half-duplex, audio, signalling and data processing IC for use in Marine VHF radio systems. Comprehensive audio processing facilities include complete audio processing, filtering, pre- or de- emphasis and frequency inversion scrambling. Signal routing and filtering is included to assist host C based signal encoding/decoding applications. 1200bps Digital Selcall (DSC) or Automatic Transmitter Identification System (ATIS) modem with protocol support and NWR decoding are supported. A DTMF encoder/decoder, a full complement of auxiliary ADCs and DACs and dual synthesised clock outputs are included in this low power PMR processor. The device also has flexible powersaving modes and is available in 48-pin VQFN and LQFP packages. 2017 CML Microsystems Plc Marine VHF Audio and Signalling Processor CMX885 2017 CML Microsystems Plc 2 D/885/4