TissueLink Aquamantys System, Руководство по обслуживанию

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4-5
RF Generator Circuit Board (RFGEN_TL1).
The RF generator PCB comprises all components of an RF device and
also the voltage regulator for the pump motor.
Power is fed in via the “from power supply” input on the power
supply PCB (Supply_TL1). Fixed voltage regulators reduce the
supplied low voltages (+/- 25V) to +5 V (for the microcontrollers
and the display) and +/-15 V for the small signal components.
“U1_Voltage Regulator” provides the variable voltage (0 to 100 V)
for the RF generator.
The RF output voltage is directly proportional to the U1 voltage. The
output power is measured and the U1 operating voltage
automatically reduced if the set power is exceeded. The same
happens when the maximum current is reached. A microcontroller
(MPU0) provides the values for maximum RF power, maximum RF
current and RF voltage.
The “power monitor” measures the power generated by the RF
generator and forwards the values to the 2nd microcontroller
(MPU1). The unit is turned off and an error alarm is issued if due to a
fault a power higher than the one set is measured.
The RF signal then reaches the Aquamantys disposable bipolar device
via an output transformer, the patient protection capacitor and a
socket. The bipolar device features a pushbutton for unit activation
whose actuation is indicated to MPU1 by the “switch monitor”.
The RF generator supplies a maximum RF voltage of approximately
250 Vpp and a maximum current of 3.2 A. The signal is sinusoidal
with a frequency of approximately 370 kHz.
The saline solution is metered by selecting a motor voltage
proportional to the RF power.
Each MPU circuit features one watchdog circuit in order to improve
the software security. RF signal activation is possible only if the
“safety trigger circuit” is periodically triggered.
RF generator PCB interfaces:
•
Supply PCB for RF generator PCB power supply
•
RF output socket (for connecting the unit’s applicator socket)
•
Socket for the pump motor
•
Socket for the display (power supply (5 V) and I²C bus