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d2:laser_controller

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d2:laser_controller [2019/07/19 11:19]
Michael Radunsky
d2:laser_controller [2019/07/25 10:11] (current)
Michael Radunsky
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 **Setpoint In** **Setpoint In**
  
-SETPOINT IN is an analog input. When the SETPOINT ENABLE is LOW (0 V) the SETPOINT IN voltage value sets the injection current instead of the front panel dial.  ​Zero volts sets zero current and 4 V sets the maximum value of 200 mA (500 mA for 500 mA version). ​+SETPOINT IN is an analog input. When the SETPOINT ENABLE is LOW (0 V) the SETPOINT IN voltage value sets the injection current instead of the front panel dial.  ​For current control boards VPN00153.12 and higher, zero volts sets zero current and 4 V sets the maximum value of 200 mA (500 mA for 500 mA version).  For current control boards with a lower rev than .12 for the VPN00153, 0 to 6 V is 0 to full-scale current
  
 This input is rolled off at 14 Hz, which is not much higher frequency than the front panel dial, which rolls off at 8 Hz, with a second pole at 4 Hz.  Therefore, noise can enter the circuit at this point and this input should be used with caution. ​ It is primarily intended for sweeping the current in order to measure PI curves and threshold values of laser diodes. ​ We do not recommend using this input for computer control of the injection current. This input is rolled off at 14 Hz, which is not much higher frequency than the front panel dial, which rolls off at 8 Hz, with a second pole at 4 Hz.  Therefore, noise can enter the circuit at this point and this input should be used with caution. ​ It is primarily intended for sweeping the current in order to measure PI curves and threshold values of laser diodes. ​ We do not recommend using this input for computer control of the injection current.
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 When disconnected,​ the SETPOINT ENABLE is at 5 V. When disconnected,​ the SETPOINT ENABLE is at 5 V.
  
-The Servo Input on the front panel continues to function when the SETPOINT ENABLE is pulled low.+The Servo Input on the front panel continues to function when the SETPOINT ENABLE is pulled low.  Only the Coarse and Fine Current Adjustments are disabled.
  
 =====Turning on the Laser Diode===== =====Turning on the Laser Diode=====
d2/laser_controller.txt · Last modified: 2019/07/25 10:11 by Michael Radunsky