X-Ray Bolometer Readout

A NI-RIO(FPGA) board is used to acquire x-ray bolometer signals. You can view the poster to read more about the motivation and application.

Some features:

• Maximum 200kSample/s analog input, filtering an smoothing
• Fixed size pre-trigger buffer and configurable post-trigger samples (DMA-transfer)
• Individual external or signal threshold trigger on rising or falling edge.

The FPGA-VI samples the bolometer signals (maximal eight analog input channel on NI-7831R) with a configurable sample frequency. The signal can be filtered (smoothed) and the resulting pretrigger data is stored in an ring buffer (4096 elements devided by the number of channels to be used) filled at least once before accepting a trigger. Trigger can be external or signal threshold with rising or falling edge. After detection of a trigger the pre-trigger and configurable number of post-trigger samples become transfered to the host via DMA.

The Host-VI reconstructs the signal and sends complete waveforms to a consumer VI via queue. It checks a command queue for configuration change requests, basically trigger configuration.

A template Consumer-VI serves as base for custom application development.

• Frontpanel of the Consumer Example:
  

• Blockdiagram of the Consumer Example:
  

• First measurement results: Pulse height spectra of an americium source.
  
  

LabVIEW 2010 sources are available in our subversion repository X-Ray cRIO and LambShift. Revision 7615 is Release 1.1

-- HolgerBrand - 12 Aug 2011