NIIS Electronics

“ Leach Controller ”



The focal plane is controlled via a SDSU Gen-II Controller designed and built by Bob Leach of Astronomical Research Cameras. It also uses a set of pre-amp cards and co-adder boards from IR-Labs. The combination allows the entire 2048x2048 Hawaii-II array to be read in about 0.1 second. The Gen-II controller is highly versatile. In particular, custom waveforms for each detector array can be downloaded to the controller using a computer interface. This allows for selectable regions of interest, on-chip binning, etc. Initial tests and characterization of the controller are now complete.




Here is the paper by Leach and Low (.pdf format): CCD and IR array controllers





The Controller consists of the following main components:

  • Timing Board: provides digital timing (or sequencing) signals for controlling the array, and communticaions with the host computer interface board.
  • Clock Driver Board: translates digital timing signals from the sequencer to controlled voltage levels for driving array clock lines.
  • Video Processor Board: amplifies and digitizes video signals from the array.
  • Utility Board: provides miscellaneous system support functions.
  • Parallel Cable Interface (PCI) Board: interfaces the timing board via parallel cable to PCI bus computers.
  • Power Control Board
  • IR Co-adder Board
  • Power Supply: provides linear and robust power for all required power.
  • Host Computer and Control Program



  • Photos of the Controller:


    Figure 1: Video Process Board (top side)


    Figure 2: Video Process Board (bottom side)


    Figure 4: The Back Side of the Controller


    Figure 5: The Inner connectors that are connected to the back plate and connect on the back side shown in Figure 4.


    Figure 6: The back plate of the controller




    Figure 7: The Front of the controller without the exterior plate


    Figure 8: A side view of the front of the controller