THORLABS MNA601/IR, Руководство пользователя

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28 HA0118T Rev 6 Feb 2016
Chapter 3
If All Ranges is selected, the unit visits all ranges when ranging between two input
signal levels.
If Odd Ranges (or Even Ranges ) is selected, only those odd (or even) numbered
ranges between the two input signals levels will be visited. These latter two modes
are useful when large rapid input signal fluctuations are anticipated. This is
because the number of ranges visited is halved to give a more rapid response.
Auto Range Change Limits - When autoranging, the NanoTrak unit adjusts continually
the TIA range as appropriate for the input signal level. When the relative signal on a
particular range drifts below the limit set in the ‘Lower’ parameter, the NanoTrak unit
decrements the range to the next lower setting. Similarly, when the relative signal
rises above the limit specified in the ‘Upper’ parameter, the unit increments the range
to the next higher setting.
Settings are entered as a percentage of full range.
Settle Samples – This parameter determines the amount of averaging applied to the
signal before autoranging takes place. Higher SettleSamples values improve the
signal to noise ratio when dealing with noisy feedback signals. However, higher
SettleSamples values also slow down the autoranging response. In a particular
application, the SettleSamples value should be adjusted to obtain the best
autoranging response combined with a noise free signal.
Values can be set from ‘2’ to ‘32’, with a default setting value of ‘4’.
Low Pass Filter - This setting specifies the cut off frequency of the digital low pass
(LP) filter applied to output readings of the internal amplifier (TIA) circuitry. If the
readings displayed or returned are unstable, this setting can be used to remove any
unwanted high frequency components and improve input signal stability.
NONE - Low pass filter inactive 10HZ - Cut off all signals above 10Hz
1HZ - Cut off all signals above 1Hz 30HZ - Cut off all signals above 30Hz
3HZ - Cut off all signals above 3Hz 100HZ - Cut off all signals above 100Hz
Note
The Upper limit must be higher than the Lower limit. If an attempt is made
to enter a value for the Lower limit which is higher than the Upper limit,
an error message is generated.
Note
This low pass filter setting is different to the low pass filter specified
using the HV Amps tab or the SetAmpOutputParams method.