Clear-Com 4000 series II, Technical Manual

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4000 Digital Series
II
Issue 2.1 Technical Manual
STA0381 Page 61
3.7 PDE 4535 Panel Electronics Card
Figure 55 - PDE4535 Panel Electronics Card
The PDE4535 is the panel processor card for non-19" 4000 series II panels.
It provides microphone amplifier/loudspeaker amplifier/power supply/processor/memory and control
interfaces.
3.7.1 PDE4535 Circuit description
U8 is the microphone amplifier 30 to 60dBs of gain, which is software selectable by U6. Up to two
microphones can be connected to CON3 & 4, one of which is software selectable at any one time via U7.
Note: Both microphone circuits are factory fitted as unbalanced with 12V phantom power.
U9 & 10 provide another 20dB gain and a limiting circuit of 8dBu.
U12 provides a balanced output for the matrix
U16 is the loudspeaker amplifier.
U11B provides software selectable loudspeaker mute and TR2 software selectable 12dBs of
loudspeaker dim.
U14 is the headphone amplifier, which has a jumper patch (LK10), for selecting left and right audio
inputs to left and right earpieces. Sidetone is software selectable via U11A and U11D.
U15D converts balanced audio from the matrix and U15C mixes it with audio from the panel options
cards (PDE4536/PDE4537/PDE3561). Analogue level controls (100K linear potentiometers) can be
fitted to CON14 and 15.
U2 is the 5V switching regulator. It takes 24Volts in via CON2.
It is synchronised with the main CPU clock and a power fail flag is provided to the CPU to allow
emergency data saving.
U3 pr12V for the analogue electronics and TR1/U4/U29 provide a -7.5V rail.
U17 is the 68000 control CPU, which runs bootstrap code, fitted at U18 and non-volatile downloaded
code from the matrix stored in U22.
U19 is a 1Mbit static ram for all volatile data.
U25 is a dual channel UART, one channel for serial communication with the matrix and the other a
spare.
U26 is an FPGA, the function of which is programmable and stored as part of the bootstrap Prom.
This board provides all necessary decode logic for the following connectors:
CON7 is for a display interface.
CON8 is for the GPI interface.
CON10 is the extension panel interface.
CON11 is the PDE4536 interface.
CON13 is an RJ45 interface to the matrix.