Technalogix TAVD-500, Руководство пользователя

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Technalogix Ltd TAVD-500 Transmitter
VI-2
The hardware of the User Interface module is based around a microcontroller (U112). This
microcontroller interfaces directly with the LCD and the membrane switch to provide output and
receive input from the user. The microcontroller also communicates with the Coupler
Conditioning board over a Controller Area Network (CAN) bus. This communication is
facilitated by two ICs, U113 and U114, and passes through a CAT5 cable attached to connector
J106. The communication link with the Coupler Conditioning module allows the User Interface
module to receive information about the forward power, reflected power, and temperature of the
transmitter, as well as relay commands from the user to the rest of the system. If the transmitter
includes more than one amplifier enclosure, a second CAN connection will be present between
the User Interface module (J105) and the TxNET board to facilitate communication between
enclosures.
Other elements of the User Interface module are also controlled by the microcontroller. A
buzzer (BZ101), a status LED (D113), and a relay to control the backlight of the LCD (RL101),
are all controlled through a buffer (U116). In order for the User Interface module to monitor the
current draw of each pallet in the system, the DC supply wires pass through the User Interface
module on their way from the power supply to the pallets. The DC enters through connector
J101 (6-position) from the power supply, and exits through J102 (10-position) to go to the
pallets. As the current passes through shunt resistors (R117/R118, R120/R121, R123/R124,
R126/R127, R129/R130), the voltage drop is monitored by U101 through U105, buffered by
U106 through U108, and sent to the analog to digital converter integrated into the
microcontroller. There are up to five circuits for which the current is monitored by this system.
As the DC supply passes through the User Interface module, it undergoes filtering to ensure
that the supply to the pallets is as clean as possible. Each of the five circuits passes through a
network of transient voltage suppressors, capacitors, and inductors. Each connection is also
fused at the input to insure an over-current condition does not persist. The fuses are a
replaceable mini blade type fuse with a 42V voltage rating, and a current rating depending on
application.
Coupler Conditioning Module
The Coupler Conditioning module serves to monitor the output of the directional coupler which
provides a voltage proportional to the forward and reflected power at the output of the
transmitter. The Coupler Conditioning module also interfaces with each of the other boards in
the control system, acting as the hub of communications for the system. Lastly, the Coupler
Conditioning board sends and receives signals through the remote access port, via the TxNET
board.
The analog signals produced by the coupler for forward and reflected power are passed onto
the Coupler Conditioning module by connectors J206 and J207, respectively. Each signal is
then filtered by LC networks. The analog signals are converted to digital by an analog-to-digital
converter integrated into the microcontroller U202.