CML Semiconductor Products
CTCSS/DCS/SELCALL Processor
FX828
D/828/4 August 2009
Provisional Issue
1.0
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Features
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Fast CTCSS Detection
Full 23/24 Bit DCS Codec
Non-Predictive Tone Detection
Low Power 3.3V/5V Operation
Variable Gain Audio Filter
Programmable Tone Decoder
Programmable Comparator for RSSI
Programmable Modulator Drivers
Programmable Tone Encoders
Full Duplex CTCSS and Selcall
1.1
Brief Description
The FX828 is an innovative CTCSS, DCS and Selcall Codec, designed for the latest generation of Land
Mobile Radio equipment. Designed to complement the FX829, the FX828 has many advanced features
which assist the operation of modern SUBAUDIO and INBAND based signalling systems. The FX828 is
electrically, physically and software compatible with the FX818 and FX829. It permits manufacturers to
add new features to their equipment with minimal design changes.
The FX828 incorporates a programmable tone decoder which can be set to respond to between 1 and 15
CTCSS or Selcall tones with minimum software intervention. In addition, a 'Fast' CTCSS detector can
respond to a single programmed tone in 60 ms, or can be used to provide an output if any CTCSS tone is
present at the detector input. Two high resolution tone encoders perform accurate generation of any
CTCSS or Selcall tone in current use. Full 23 or 24 bit DCS encoding and decoding complements the
CTCSS/Selcall line-up. A timer is included which, for example, may be used for timing Selcall
transmissions and a comparator is provided to assist with carrier or RSSI monitoring. The device can
operate full duplex in all operating modes except for DCS.
The FX828 along with the FX818 and FX829 is offered in a choice of small SSOP, DIL and SOIC 24-pin
packages. It may be used with 3.0 to 5.5 volt supply.
©
2009 CML Microsystems Plc
CMLMICRO [ CML MICROCIRCUITS ]
