note: see file for amplifier overview
There is a broadband amplifier board (used to read signals from a special kind of photodiode) which needs some additional components. Basically, a comparator which has an adjustable threshold must be added. The analog signal output as it is now has peaks from 0 to -1.5 V roughly, with a width of ~30 ns (negative pulses, kind of Gaussian shape). About 10^6 to 10^7 pulses come per second from the diode. The threshold should be adjustable from roughly -0.1 to -1.5 V using a potentiometer.
The original design files are in P-CAD format, which must first be imported into Altium Designer (there is a way to do this, but it might not be completely automatic, I don't know). The comparator circuit must be designed and added to the original board PCB design (by making the board longer, and wider if necessary) and a digital output SMC jack position must be added. In other words, there should be both an analog and digital output. If needed, a +5 and/or -5 V can be added to power the comparator. Potential comparators include the LMH6624 and the LMV7219, although others can be considered.
A summary of the work steps is below:
1. Import P-CAD files into Altium Designer, export files in Altium Designer format (send files)
2. Design comparator circuit (send schematic to be checked before proceeding)
3. Design PCB layout (send files of design to be checked)
4. Assemble complete parts list from digi-key