Charleston Lake
Astronomical
Imaging the Night Sky from Ontario Canada
SBIG ST8300M - Technical 
SBIG ST8300M CCD Camera

OPERATION NOTES / RECOMMENDATIONS:
  a) Never unplug the 12V from the camera without first powering down the DC supply 
  b) Drivers are done with SBIG Universal Driver. This seems to be an effort by SBIG to simplify driver installation, but,  
      it can lead to issues, as the Driver Checker will load new drivers, and it can be difficult to find the previous  
      version.
  c) When you have a working system, it is recommended that you record and backup your drivers, so that you have  
      a baseline to go back to, if a future driver update causes issues.
  d) Some users had the USB connector break at the circuit board if the cables get yanked. Support the cable  
      always!!
  e) Don't store the camera wet with dew. Dry it out after a night of imaging. The circuitry, connectors, can degrade
      and fail if the camera is not dried out before storage. Especially if in a salty air environment.
   f) Set the sub-frame exposure duration such that the ADU count remains below saturation of 65K for best results. If
      you desire more data, add more (non-saturated) sub-frames, rather than lengthen the sub-frame exposure. 
CCD in circuit
XILINX FPGA Chip
KAF-8300 CCD
DATA CLOCKING
ST8300M - Electronic / Circuit notes
 
Some technical Details for the ST8300M camera... (note - this is an overview only)
Power Regulation, bus supply is performed by (two) CINCON DC-DC converters. One generates +/- 12VDC from the incoming user power, the other generates +3.3VDC. 

The ST8300M uses a XILINX Spartan-II XC2S50 FPGA for control / timing / CCD clocking. The FPGA has 24,576 bits distributed RAM, 32K bits Block RAM, 384 CLBs (Configurable Logic Blocks). This is custom programmed, specific to the SBIG ST8300 camera. This FPGA clocks the data out of the CCD chip, and synchronizes the data with the other digital circuitry downstream from the A-D converter. FPGA's are flexible, deterministic and faster than a uProcessor.

The analog data from the CCD (Pin 7 VOut) is amplified via an Analog Devices AD8024AR Quad current feedback Op-Amp chip. The analog data is clocked out, amplified, then into a 16bit A-D converter, converting the analog data from the CCD to the digital data bus. The (now digital) CCD bus data goes into a buffer, Renesas IDT7206 CMOS ASYNCHRONOUS FIFO. An EEPROM is in the circuit, ATMEL ATF1502ASV CPLD (3.3v)

The camera uses a Cypress CY7C68013A 128 pin USB2.0 controller chip, which has an 8051 microprocessor internal, to interface to the PC via USB. This chip uses bi-directional data, control from the PC, and image data returned from the camera. This is the most probable integrated circuit failure in the camera, if power is unplugged live.

The Shutter is rotated by a NPM Stepper motor, PF25-48F4. This stepper motor is custom to SBIG, due to the mechanical shaft length. The motor is 7.5deg/step, 50ohm coils, Unipolar. It has 4 different configurable phases, which determine the stepper coil firing. This is set via CCDOps software. The stepper motor is driven by a dedicated driver chip on the ST8300 circuit board. The timing is controlled by the FPGA. The rotary shutter is dependable, the stepper motor MTBF is millions of cycles.

The circuit board is multi-layer, and the component density is high. As such, it does not lend itself to "average skill" user repair, without specialized equipment and knowledge. Due to it's age, some of the components are obsolete making replacement components difficult to source.

Summary
Overall, despite it's age, the ST8300M is still a very capable camera. Noise, with the Peltier cooled KAF-8300 CCD chip, is very low. The small pixel size of 5.4um makes this camera a good candidate for wide-field refractors, the sampling is about perfect on a 600-700mm focal length telescope.  

If properly maintained, and recommended procedures followed, this camera can last for many years.
 
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