Photolysis Controller

A complete system for experiment control and data acquisition has been designed and manufactured. Also the firmware and software has been prepared to fulfill all the customer needs. The system serves for laser photolysis examination of different biological samples.

The equipment can control a few external devices required:

  • electromechanical shutter for xenon lamp (on/off),
  • monochromator (RS232 port),
  • nanosecond laser (TTL pulses with microsecond precision),
  • photomultiplier (high voltage control and monitoring, supply current monitoring and backoff compensation).

The main board comprises of several fundamental devices:

  • integrated high voltage power supply for photomultiplier and set of precision ADCs and DACs for its control,
  • fast 400 MSps 14-bit ADC converter for acquisition of wide-band signals (pulses) from photomultiplier,
  • module with Xilinx Zynq 7020 FPGA/ARM device.

The device front panel contains a number of connectors: two RS232 sockets, four BNC (TTL) connectors (laser, shutter) and an integrated, specialized socket for photomultiplier (high-band signal, control and high voltage). On a back panel there are USB and Ethernet connectors, and an AC power supply socket. A multi-voltage, low-noise power supply is a substantial part of the design.

The system allows for digitalized signal acquisition at 10 different speeds, from 500 kSps (8ms buffer length) upto 400 MSps (10us buffer length). The signal from the photomultiplier is appriopriately digitally filtered for speeds slower then maximal. The acquired data are transmitted over Ethernet to the control computer, running LabVIEW software which controlls the whole experiment and presents the data.