Utah Medical Products FINESSE +, Руководство по обслуживанию

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Service Manual
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between the hand switch wires and the generator logic elements. Between periods of surgical
activity the comparator outputs are low and the optical isolators stay in the "off" condition. When
one of the two hand switch buttons is activated, the corresponding comparator toggles high and
the optical isolator switches "on". When current flows through either of these optical isolators,
the CPLD is instructed to activate the 450 kHz oscillator, select the appropriate PWM voltages,
produce the correct cut/blend or coag waveforms, and activate the vacuum motor.
The footswitch operates an isolated circuit that is identical to the handswitching circuit.
CQM/Pad Detect Circuitry
The is capable of using either standard (solid or single) or CQM (split or dual) dispersive
pads. The CPLD generates a 39.5kHz clock signal that is buffered, filtered, and used to drive the
pad detect hardware. The Logic Board produces a DC voltage that directly relates to impedance
of the 39.5kHz signal between pad surfaces. The microprocessor assesses this DC voltage and the
status of the mechanical pad detect switch (located in the pad receptacle), and determines
whether the signal is at a level appropriate for a standard or CQM pad. If a CQM pad is detected,
the microprocessor considers the DC voltage a CQM status signal, and calculates an error
threshold level from this DC voltage that corresponds to roughly 25%-30% pad surface
detachment. When the CQM signal level reaches the error level threshold, the system will display
an error and discontinue output until the condition can be corrected. The microprocessor
continuously monitors the CQM signal and is also able to set a new, lower threshold if better
conditions are encountered.
The acceptable resistance ranges of a standard pad and CQM pad do not overlap, and therefore
the provides a redundant level of pad type detection for reliability.
Display Board and Front Panel Controls
The display board contains only indicator lights and the cut/blend and coag mode user controls.
All displays are controlled by the CPLD and/or microprocessor. The cut and coag mode controls
are potentiometers that relay a DC voltage to the microprocessor, while the mode select switch is
wired directly to the CPLD.