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micromirror [2016/10/04 15:13]
127.0.0.1 external edit
micromirror [2017/08/17 10:26] (current)
jon [Shortcomings of the Drive Card]
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 ===== Shortcomings of the Drive Card ===== ===== Shortcomings of the Drive Card =====
    
-No calibration has been performed to make sure the relationship between the applied input voltage (in external input mode) or between the axis positions (in internal input mode) are accurate. ​ However we can make a rough guess based on the micro-mirror specifications of 9.2degrees for 131V; with analog multiplication of 20x we expect each volt of analog input (in external mode) to move the mirror by approximately \begin{equation} \frac{20V}{131V}×9.2º = 1.4º\end{equation}. ​ We expect the user to cross-calibrate the move amount with a corresponding stage movementthe DACK command ​can also be used to set a scale factor for calibration.+No calibration has been performed to make sure the relationship between the applied input voltage (in external input mode) or between the axis positions (in internal input mode) are accurate. ​ However we can make a rough guess based on the micro-mirror specifications of 9.2degrees for 131V; with analog multiplication of 20x we expect each volt of analog input (in external mode) to move the mirror by approximately \begin{equation} \frac{20V}{131V}×9.2º = 1.4º\end{equation}. ​ We expect the user to cross-calibrate the move amount with a corresponding stage movement.  Before firmware v3.14 the DACK command ​could be used to set a scale factor for calibration, but starting with v3.14 it is assumed that the user will instead adjust the move position or single-axis amplitude accordingly.
  
 Until and including version C of the Drive Card, the high-voltage amplifiers get very hot due to their quiescent current. ​ In later versions of the card this issue is addressed by changing amplifier ICs.  Occasionally cards (version C and before) fail due to overheating,​ so it is advised to turn of the TG-1000 controller when not in use.  Contact ASI for assistance if the MicroMirror Drive Card appears to fail entirely (all the output pins on the DB9 connector to the Scanner will be 0V in that case). Until and including version C of the Drive Card, the high-voltage amplifiers get very hot due to their quiescent current. ​ In later versions of the card this issue is addressed by changing amplifier ICs.  Occasionally cards (version C and before) fail due to overheating,​ so it is advised to turn of the TG-1000 controller when not in use.  Contact ASI for assistance if the MicroMirror Drive Card appears to fail entirely (all the output pins on the DB9 connector to the Scanner will be 0V in that case).
micromirror.txt · Last modified: 2017/08/17 10:26 by jon