INFICON MDC-370 Thin Film Deposition Controller - Manual (Page 40)

MDC-370 DEPOSITION CONTROLLER
Crystals parameter defines the number of crystals in the sensor head.
The Rotator Delay parameter defines the maximum amount of time
allowed for the correct crystal to rotate into position. This should be
set to the time it takes for the rotator to go from crystal #1 all the way
around to crystal #1 again.
The settings of the three remaining parameters required for automatic
crystal position control depend on the type of position control and
position feedback.
Position Control - The MDC-370 can be setup to either control the
crystal position directly by interfacing to the rotator’s actuator or
indirectly by interfacing to a rotator controller.
Direct Control of Pocket Position - Direct control means that the
MDC-370 will control the actuator (rotator motor, pneumatic
valve, etc.) directly to get the desired crystal into position. For
direct control, set the Control Parameter to Direct then select
one of the following drive types and follow the instructions:
a. Unidirectional Motor Drive - Select Up for the Drive
parameter. A relay output will be created called “SensorN
Drive Up” that should be connected between the rotator
motor and power supply.
b. Bi-directional Motor Drive - Select Fast for the Drive
parameter. Two relay outputs will be created. One called
“SensorN Drive Up” and one called “SensorN Drive Dn”.
With this drive type, the MDC-370 will activate either the
drive up or drive down outputs to get to the required crystal
in the least amount of time.
d. Unidirectional Pneumatic Drive - Select Sngl Step or Dbl
Step for the Drive parameter. A relay output will be created
called “SensorN Drive Up” that should be connected
between the rotator’s pneumatic valve and power supply.
With Sngl Step, the output will pulse once for one second to
increment the rotator one position. With Dbl Step, the
output will pulse twice for one second each to increment the
rotator one position.
Indirect Control of Crystal Position - Indirect control means that the MDC-
370 will indicate the desired crystal position to a crystal rotator controller
through position select outputs. . The Drive parameter selects between the
two following indirect position output formats:
a. Individual - With individual format, one output will be created
for each crystal. So, if crystal 2 is the desired crystal, then the
output “SensorN Crystal2” will be true while all the other position
outputs will be false.
PROGRAMMING AND CONTROLLER SETUP 4-8