Codan NGT 2010 RF Technical & Service Manual page 133

IC15 is an EPLD used for address decoding and controlling the CAN controller IC17.
IC16 is another flash memory device that contains all the channel information as well as
the ALE link quality statistics.
The audio interface device IC5 (sheet 1) receives audio on pin 28, then converts this to
14-bit data. The 14-bit data is processed in IC3 and then converted back to audio and
output through IC7/A. The audio is then fed to the Audio Interface PCB.
The reset device IC2 resets the microprocessor if the 5 V supply drops below
approximately 4.7 V.
Audio Interface PCB
Drawing
IC12 is in Sleep mode when no data is present. When data is received from Application
Processor IC4, the RC oscillator starts to run and 'wakes up' IC12.
IC12 then controls the power off, and drives the diagnostic LED H1. It also controls the
EPLD IC11, which samples the CIB audio TDM channels and generates the
synchronisation pulse.
RF/IF PCB
Drawing
ALTERNATIVE TEXT
Drawing
NOTE
IC405 (04-03106) or IC408 (04-03378) is in Sleep mode when no data is present. When
data is received from Application Processor IC4, the RC oscillator starts to run and
'wakes up' IC405/IC408.
IC405/IC408 then programs the phase lock loop and the DDS ICs depending on the
channel frequency required. It also controls the transmit/receive switching functions,
filter select, AGC time constants and other ancillary functions.
NGT Transceiver System Technical Service Manual
04-03109
04-03106 (sheet 3), or
04-03378 (sheet 3)
If the PCB issue status is -06 or earlier, see drawing
NGT—Technical description (2010)
04-03378 (sheet 3).
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