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slice:dcc [2019/09/24 15:13]
Michael Radunsky [Error States]
slice:dcc [2020/04/30 16:54] (current)
Michael Radunsky [Laser and Photodiode Connections]
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   * SLICE-DCC dual-channel Current Controller   * SLICE-DCC dual-channel Current Controller
   * AC power cord with appropriate wall plug for you location (if known)   * AC power cord with appropriate wall plug for you location (if known)
-  * Two 6 ft SMA cables 
   * One BNC grounding cap for door safety interlock   * One BNC grounding cap for door safety interlock
   * Two keys for lock out   * Two keys for lock out
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 ===== Proper Usage ===== ===== Proper Usage =====
 <WRAP center round box 60%> <WRAP center round box 60%>
-| {{ :warning-sign.png?200&nolink }}  | If this instrument is used in a manner not specified by the manufacturer in this manual or other relevant literature, protection provided by the instrument may be impaired. | +| {{ :warning-sign.png?200&nolink }}  | If this instrument is used in a manner not specified by the manufacturer in this manual or other relevant literature, protection provided by the instrument may be impaired.                                                                                  
-| {{ :warning-sign.png?200&nolink }}  | Use caution when connecting the SLICE-DCC to your diode Diode lasers are static sensitive and can be damaged from static build up. Make sure to discharge any charge built up on your skin or clothes by using a grounding strap while making connections.  |+| {{ :warning-sign.png?200&nolink }}  | Use caution when connecting the SLICE-DCC to your diode Diode lasers are static sensitive and can be damaged from static build up. Make sure to discharge any charge built up on your skin or clothes by using a grounding strap while making connections.  |
 </WRAP> </WRAP>
 \\ \\
    
 <WRAP center round important 100%> <WRAP center round important 100%>
-The SLICE-DCC is designed to drive, among other devices, laser diodes.  In order to be in US FDA compliance for driving lasers:\\ +The SLICE-DCC is designed to drive, among other devices, laser diodes, quantum cascade lasers, and semiconductor amplifiers.  In order to be in US FDA compliance for driving lasers:\\ 
  
   * There is a 5 s delay between turning on the current and the current beginning to flow.  During this period, a warning light will flash on the front panel of the SLICE-DCC.   * There is a 5 s delay between turning on the current and the current beginning to flow.  During this period, a warning light will flash on the front panel of the SLICE-DCC.
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 | Control                                                              |  Touch Screen, GUI, Serial commands     | | Control                                                              |  Touch Screen, GUI, Serial commands     |
 | Operation Modes                                                      |  Constant Current\\ Constant Power      | | Operation Modes                                                      |  Constant Current\\ Constant Power      |
-| \\ \\ Maximum Current                                                |  200 mA\\ 500 mA\\ 1 A\\ 2 A            +| \\ \\ Maximum Current                                                |  200 mA\\ 500 mA\\ 1,000 A\\ 2,000 mA   
-| \\ \\ Current Noise((Constant Current Mode)) ((rms 10 Hz to 1 MHz))  |  1.5\\ 4\\ 10\\ 15                      | +| \\ \\ Current Noise((Constant Current Mode)) ((rms 100 Hz to 1 MHz))  |  1.5\\ 4\\ 10\\ 15                      
-| Modulation Bandwidth((3 dB))                                         |  DC to >1 MHz                           +| Current Modulation Input Impedance \\ Rear \\ Front  |  \\ >20 kΩ\\ 50 Ω or 1 MΩ  
-| Modulation Depth                                                     |  ±10 mA                                 +| Modulation Bandwidth((-3 dB point)), ((front & rear modulation input ports))|  DC to >1 MHz                
-| Modulation Transfer Function                                         |  1 mA/V                                 |+|Modulation Depth          \\ SLICE-DCC-200\\ SLICE-DCC-500\\ SLICE-DCC-1000\\ SLICE-DCC-2000 |  \\ ±10 mA\\ ±25 mA\\ ±50 mA\\ ±50 mA  
 +|Modulation Transfer Function  \\ SLICE-DCC-200\\ SLICE-DCC-500\\ SLICE-DCC-1000\\ SLICE-DCC-2000 |  \\ 1 mA/V \\ 2.5 mA/V \\ 5 mA/V \\ 5 mA/V  |
 | Modulation Input Range                                                ±10 V                                  | | Modulation Input Range                                                ±10 V                                  |
 | Current Resolution                                                    100 µA                                 | | Current Resolution                                                    100 µA                                 |
 | Drift                                                                |  <25 µA/°C                              | | Drift                                                                |  <25 µA/°C                              |
 | Power Stability((constant power mode))                                0.1% rms((relative to maximum power))  | | Power Stability((constant power mode))                                0.1% rms((relative to maximum power))  |
 +| Monitor Photodiode Input Current Range  | ±5 mA |
 | Maximum Compliance Voltage                                            12 V                                   | | Maximum Compliance Voltage                                            12 V                                   |
 | Triggering                                                            TTL                                    | | Triggering                                                            TTL                                    |
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   - Door interlock   - Door interlock
   - CH 2 Current output   - CH 2 Current output
-  - CH 2 Modulation input+  - [[:slice:dcc#rear-panel_modulation|CH 2 Modulation input]]
   - CH 2 Photodiode input   - CH 2 Photodiode input
  
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 The touch screen interface and the Host GUI operate in a substantially similar way, except touch is substituted for a click in the touch screen interface. The touch screen interface and the Host GUI operate in a substantially similar way, except touch is substituted for a click in the touch screen interface.
  
-When presented with a given view, it is possible to select the functionality or edit the values in a field bordered in <color black/hsl(213, 80%, 60%)>blue</color> When a particular field is actively being edited, its border will change to <color black/yellow>yellow</color>. +When presented with a given view, it is possible to select the functionality or edit the values in a field bordered in <color black/hsl(213, 80%, 60%)>blue</color> When a particular field is actively being edited, its border will change to <color black/yellow>yellow</color> The Home Screen of the SLICE-DCC is shown in <imgref home_scr_dcc> and is reached by clicking the home button (<imgref home_butt>) in the upper left corner of the touch screen. From the Home screen, summary control over the two channels is possible, including setting I<sub>set</sub> or P<sub>set</sub>,From the Home screen, you can edit the control parameters for each channel.
-The Home Screen of the SLICE-DCC is shown in <imgref home_scr_dcc> and is reached by clicking the home button (<imgref home_butt>) in the upper left corner of the touch screen. From the Home screen, summary control over the two channels is possible, including setting I<sub>set</sub> or P<sub>set</sub>,From the Home screen, you can edit the the control parameters for each channel.+
  
 In general, the status displayed in an editable field is the current status (not the result of touching the button).  Touch the field to select a new value/status.  For instance, in <imgref home_scr_dcc> both channels are in stand by.  Touching the OFF button will initiate current delivery to the given channel.\\ In general, the status displayed in an editable field is the current status (not the result of touching the button).  Touch the field to select a new value/status.  For instance, in <imgref home_scr_dcc> both channels are in stand by.  Touching the OFF button will initiate current delivery to the given channel.\\
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 ==== Home Button ==== ==== Home Button ====
 <imgcaption home_butt|Home button>{{ :slice:slice-qt-home-button.gif?77x75 |}}</imgcaption> <imgcaption home_butt|Home button>{{ :slice:slice-qt-home-button.gif?77x75 |}}</imgcaption>
-Returns to [[#Home Screen|Home screen]] (<imgref home_scr>).+Returns to [[#Home Screen|Home screen]] (<imgref home_scr_dcc>).
 ==== Back Button ==== ==== Back Button ====
 <imgcaption back_butt|Back button>{{ :slice:slice-qt-back-button.gif?77x75 |}}</imgcaption> <imgcaption back_butt|Back button>{{ :slice:slice-qt-back-button.gif?77x75 |}}</imgcaption>
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 ===== SLICE-DCC Operation ===== ===== SLICE-DCC Operation =====
 The Home screen displays the status of both channels (<imgref home_scr_dcc>).  The data for each channel is arranged vertically.   At a glance, for each channel, I<sub>set</sub>, and Compliance Voltage can be read.  Touching the blue window labelled Voltage [V] will cause this window to toggle from displaying  Compliance Voltage to displaying dissipated Power. The Home screen displays the status of both channels (<imgref home_scr_dcc>).  The data for each channel is arranged vertically.   At a glance, for each channel, I<sub>set</sub>, and Compliance Voltage can be read.  Touching the blue window labelled Voltage [V] will cause this window to toggle from displaying  Compliance Voltage to displaying dissipated Power.
 +==== Laser and Photodiode Connections ====
 +
 +=== Connection to Laser Diode ===
 +The SLICE-DCC requires that the cathode of the laser diode is at ground (<imgref cath_gnd>).  The anode is connected to the center conductor of the SMA connector on the rear of the SLICE-DCC and the cathode is connected to the sheath.
 +
 +<imgcaption cath_gnd|Wiring configuration for laser diode>{{ :slice:dcc:cathode_ground.png?430 |}}</imgcaption>
 +
 +=== Connection to Monitor Photodiode ===
 +Either of the two configurations of the monitor photodiode seen in <imgref mon_pd> will work for the signal proportional to the laser diode power for operating in Constant Power mode.  Depending on how you have completed the monitor photodiode circuit, you may have to adjust the [[slice:dcc#constant_power_mode|sign of the Constant Power feedback loop]].
 +
 +
 +<imgcaption mon_pd|Wiring configurations for monitor photodiode>{{ :slice:dcc:anode_cathode_ground_monitor_pd.png |}}</imgcaption>
 ==== Setting the Operation Mode ==== ==== Setting the Operation Mode ====
 The SLICE-DCC has two operation modes: Constant Current and Constant Power.  The operation mode, as with most other operating parameters can be set independently for each channel.  To toggle between Constant Current and Constant Power modes, from the Home screen, touch the window labelled either CH X Constant Current or CH X Constant Power.  If the channel is in Constant Current Mode, you will be presented with the window seen in <imgref cc_param>. \\ The SLICE-DCC has two operation modes: Constant Current and Constant Power.  The operation mode, as with most other operating parameters can be set independently for each channel.  To toggle between Constant Current and Constant Power modes, from the Home screen, touch the window labelled either CH X Constant Current or CH X Constant Power.  If the channel is in Constant Current Mode, you will be presented with the window seen in <imgref cc_param>. \\
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 Touching the Window labeled Control Mode will allow you to toggle the channel back & forth between Constant Current and Constant Power modes as seen in <imgref cc_cp>. Touching the Window labeled Control Mode will allow you to toggle the channel back & forth between Constant Current and Constant Power modes as seen in <imgref cc_cp>.
  
-<imgcaption cc_cp>|Constant Current or Constant Power>{{ :slice:dcc:cc_cp_toggle.png?430x254 |}}</imgcaption> \\+<imgcaption cc_cp|Constant Current or Constant Power>{{ :slice:dcc:cc_cp_toggle.png?430x254 |}}</imgcaption> \\
 ==== Setting the Current Limit ==== ==== Setting the Current Limit ====
 The user can set a maximum deliverable current so as not to exceed the rated maximum for their device.  From the Home screen, touch the window labelled either CH X Constant Current or CH X Constant Power. Depending on the operation mode, you will be presented with either <imgref cc_param> or <imgref cp_param> The user can set a maximum deliverable current so as not to exceed the rated maximum for their device.  From the Home screen, touch the window labelled either CH X Constant Current or CH X Constant Power. Depending on the operation mode, you will be presented with either <imgref cc_param> or <imgref cp_param>
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 ==== Rear-Panel Modulation ==== ==== Rear-Panel Modulation ====
-On the rear panel of the SLICE-DCC is an input for servoing or modulating the current output.  (<imgref back>, item 9).  The transfer function for this input is 1 mA/V and the input range is ±10 V.  Therefore the current can be modulated by ±10 mA.  The 3-dB bandwidth of this modulation input is DC to 1 MHz.+On the rear panel of the SLICE-DCC is an SMA input for servoing or modulating the current output.  (<imgref back>, item 9).  The transfer function for this input depends on the current capacity (see <tabref specs>).  The input range is ±10 V.  The current can be modulated over the full range of current except for the 2,000 mA model which can only swing ±500 mA.  The 3-dB bandwidth of this modulation input is DC to 1 MHz
 + 
 +It is also possible to introduce a modulation/control signal from the front-panel input BNC.  Only one input port can be active at a time.
  
 <WRAP center round box 60%> <WRAP center round box 60%>
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 | {{ :warning-sign.png?400&nolink }}  | Warning.  Make sure the Current Limit is set below the recommended maximum current for your laser diode and that the monitor photodiode is working and delivering a signal to the SLICE-DCC before engaging Constant Power mode.  If a signal proportional to the laser power from the monitor diode is not delivered to the SLICE-DCC, the current may ramp to its maximum allowed value when Constant Power mode is engaged.  | | {{ :warning-sign.png?400&nolink }}  | Warning.  Make sure the Current Limit is set below the recommended maximum current for your laser diode and that the monitor photodiode is working and delivering a signal to the SLICE-DCC before engaging Constant Power mode.  If a signal proportional to the laser power from the monitor diode is not delivered to the SLICE-DCC, the current may ramp to its maximum allowed value when Constant Power mode is engaged.  |
 </WRAP> \\ </WRAP> \\
-  - Connect the output of the monitor photodiode to the CH X Photodiode Input connector (labelled "10" in [[slice:dcc#rear_panel|the back-panel image]]) on the back of the SLICE-DCC.\\ \\ In order for Constant Power mode to operate correctly, the user must set three control parameters: the responsivity of the monitor photodiode, the gain of the loop filter, and the polarity of the photodiode response.  Before setting these control parameters. first [[slice:dcc#setting_the_operation_mode|set the SLICE-DCC in Constant Power mode]] and [[slice:dcc#setting_the_operating_power_in_constant_power_mode|set the Power Setpoint]].  From the home screen, enter the CH X Settings screen by tapping the window labelled CH X: Constant Power.  Enter values for Detector Response, Gain, and monitor photodiode Polarity. \\ \\ +  - Connect the output of the monitor photodiode to the CH X Photodiode Input connector (labelled "10" in [[slice:dcc#rear_panel|the back-panel image]]) on the back of the SLICE-DCC.\\ \\ In order for Constant Power mode to operate correctly, the user must set three control parameters: the responsivity of the monitor photodiode, the gain of the loop filter, and the polarity of the photodiode response.  Before setting these control parameters. First [[slice:dcc#setting_the_operation_mode|set the SLICE-DCC in Constant Power mode]] and [[slice:dcc#setting_the_operating_power_in_constant_power_mode|set the Power Setpoint]].  From the home screen, enter the CH X Settings screen by tapping the window labelled CH X: Constant Power.  Enter values for Detector Response, Gain, and monitor photodiode Polarity. \\ \\ 
   - Enter the value of the detector response supplied in the documentation that came with your monitor photodiode. (<imgref cp_param_set>) <imgcaption cp_param_set|Setting the detector response for Constant Power mode>{{ slice:dcc:cp_set_responsivity_knobs.png?430x254 |}}</imgcaption>    - Enter the value of the detector response supplied in the documentation that came with your monitor photodiode. (<imgref cp_param_set>) <imgcaption cp_param_set|Setting the detector response for Constant Power mode>{{ slice:dcc:cp_set_responsivity_knobs.png?430x254 |}}</imgcaption> 
   - Turn the Gain all the way to 0 (zero).  Turn the system ON to deliver current to the diode.  Slowly turn up the Gain until the power begins to oscillate (<imgref cp_gain>).  (Hint; It is easiest to adjust the gain for this step via the knobs as opposed to through the keypad.) Turn down the Gain until oscillation stops. <imgcaption cp_gain|Setting the Gain for Constant Power>{{ slice:dcc:cp_set_gain.png?430x254 |}}</imgcaption>    - Turn the Gain all the way to 0 (zero).  Turn the system ON to deliver current to the diode.  Slowly turn up the Gain until the power begins to oscillate (<imgref cp_gain>).  (Hint; It is easiest to adjust the gain for this step via the knobs as opposed to through the keypad.) Turn down the Gain until oscillation stops. <imgcaption cp_gain|Setting the Gain for Constant Power>{{ slice:dcc:cp_set_gain.png?430x254 |}}</imgcaption> 
   - If more Gain moves the power away from the set point, switch the polarity from Positive to Negative (or vice versa).   - If more Gain moves the power away from the set point, switch the polarity from Positive to Negative (or vice versa).
 ===== Programmable Input & Output ===== ===== Programmable Input & Output =====
-The SLICE-DCC has two programmable inputs (labelled A & B) and two programmable outputs (labelled 1 and 3) on the front panel.  It also has a rear panel trigger input and trigger output.  Touching the I/O window on the control bar will open a screen similar to that seen in <imgref io_main>,  From here, it is possible to assign control information input to the two inputs and system performance data to the two outputs,+The SLICE-DCC has two programmable inputs (labelled A & B) and two programmable outputs (labelled 1 and 2) on the front panel.  It also has a rear panel trigger input and trigger output.  Touching the I/O icon on the control bar will open a screen similar to that seen in <imgref io_main>,  From here, it is possible to assign control information input to the two inputs and system performance data to the two outputs,
  
 <imgcaption io_main|I/O programming window>{{ :slice:dcc:i-o_programmed.png?430x254 |}}</imgcaption> <imgcaption io_main|I/O programming window>{{ :slice:dcc:i-o_programmed.png?430x254 |}}</imgcaption>
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-==== Programmable Input ====+==== Programmable Input (Front-panel Modulation) ====
 From <imgref io_main>, if one touches either the A or B input window, the choices for input for that channel are presented (<imgref io_input>). From <imgref io_main>, if one touches either the A or B input window, the choices for input for that channel are presented (<imgref io_input>).
  
 <imgcaption io_input|Input choice for front-panel input>{{ :slice:dcc:i-o_input_equals_modulation.png?430x254 |}}</imgcaption> <imgcaption io_input|Input choice for front-panel input>{{ :slice:dcc:i-o_input_equals_modulation.png?430x254 |}}</imgcaption>
  
-At present (Aug, 2019), the only input option is a modulation signal.  The SLICE-DCC can respond to a modulation or control signal over a bandwidth of DC to 1 MHz.+The only input option is a modulation signal.  The SLICE-DCC can respond to a modulation or control signal over a bandwidth of DC to 1 MHz.  Only one of the two modulation input ports (rear-panel SMA, <imgref back>, item 9 or front-panel BNC, <imgref front>, item 2) can be active at any given time.  Activating the front-panel input via the screen in <imgref io_input> automatically disconnects the rear-panel input. 
 + 
 +The depth and index of modulation varies depending on the current capacity of the particular SLICE-DCC unit.  See <tabref specs>.
  
 ==== Programmable Output ==== ==== Programmable Output ====
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 Change the input impedance of the two front-panel input ports.  Select either 50 Ω or 1 MΩ. Change the input impedance of the two front-panel input ports.  Select either 50 Ω or 1 MΩ.
  
-=== SLICE-QT Firmware ===+=== SLICE Firmware ===
 Current firmware versions are reported here.   Current firmware versions are reported here.  
  
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 The GUI should now actively control the SLICE-DCC.  You should only have to do the above steps once from a given PC.  After assigning the COM port, the system will recognize the device in the future (unless you reassign the COM port to another device). The GUI should now actively control the SLICE-DCC.  You should only have to do the above steps once from a given PC.  After assigning the COM port, the system will recognize the device in the future (unless you reassign the COM port to another device).
 ===== Firmware Update ===== ===== Firmware Update =====
-From time to time, Vescent will upgrade the firmware for controlling the SLICE-DCC.  The procedure to upgrade the firmware is given [[slice:dcc:firmware|here]].+From time to time, Vescent will upgrade the firmware for controlling the SLICE-DCC.  The procedure to upgrade the firmware is given [[https://github.com/Vescent|here]].
 ===== Serial API ===== ===== Serial API =====
 It is possible to control the SLICE-DCC through serial commands.  Click here to access the [[slice:dcc:API|SLICE-DCC API]]. It is possible to control the SLICE-DCC through serial commands.  Click here to access the [[slice:dcc:API|SLICE-DCC API]].
slice/dcc.1569363218.txt.gz · Last modified: 2019/09/24 15:13 by Michael Radunsky