20
HA0378T Rev C Feb 2019
Chapter 3
EXT IN (Male BNC connector)
– Used to control the piezo stage from an external
source. When in open loop the EXT IN controls the voltage, when in closed loop it
controls the position. This input allows a -10V to 10V input to drive the output to its full
scale. This gives a gain of 15 for the 150V range. The input impedence is 10 k
load.
EXT OUT (Male BNC connector)
– Used to monitor the piezo actuator on an
oscilloscope or other device. The output can be set to monitor the piezo Drive Voltage,
the Linearized Position, or the Unprocessed Position, as set in the Output Signal
parameter in the settings panel - see Section 5.2.1., or in software by calling the
SetPPCIOSettings method (see the
APTServer helpfile
available from the Windows
‘Start’ menu).
JOYSTICK -
Provides connection for the MZF001 Joystick - see Section 4.9. and
USER
- This female 15-Pin D-type connector exposes a number of internal electrical
signals. For convenience, a number of logic inputs and outputs are included, thereby
eliminating the need for extra PC based IO hardware. Using the APT support
software, these user programmable logic lines can be deployed in applications
requiring control of external devices such a relays, light sources and other auxilliary
equipment - see Section A.2. for further details.
RS232
– Provides connection for serial port communication - see Section A.3.
USB
- USB port for system communications.
Caution
Before the input can be used, the Drive Input Source must be set to a BNC
(+SW) option in the Settings panel (see Section 5.2.1.) or in software by
calling the SetPPCIOSettings method (see the
APTServer helpfile
available
from the Windows ‘Start’ menu) - see Section 4.7. for more details.
When driving the piezo stage from an external source, the external signal
is added to the software input (GUI panel or SetVoltOP software method)
and, if connected and selected, the Joystick.
The max stepping frequency depends on the shape of the waveform. E.g.
for a staircase waveform with a step size up to 25 µm, the minimum period
for each step can be as small as 25 ms or stepping frequency of 40 Hz.
For large periodic waveforms, e.g. over 200 µm peak to peak sine wave
signal, the operational frequency is recommended to be as follows:
Loads up to 50g - </= 40 Hz
Loads 50 to 150g - </= 30 Hz
Loads 150g to 300g - </= 20 Hz
Note
The USB cable length should be no more than 3 metres unless a powered
USB hub is being used.
