Difference between revisions of "IntegrationDaq 210730"

Revision as of 17:59, 29 July 2021

Back to Main Page >> Data Acquisition Meetings >> Integrating mode DAQ meetings

previous meeting << >> following meeting

Meeting information

 Meeting time:  3:30pm Eastern
 
 BlueJeans calling instructions:
 Toll-Free Number (U.S.&  Canada):  888-240-2560
 Other BlueJeans access phone numbers are listed at https://www.bluejeans.com/premium-numbers
 
 Bluejeans CODE:                    641 252 323
 Bluejeans link: https://bluejeans.com/641252323

Agenda

• Progress on prototype
• Requirements document needed. From Jim's message: "we need to get the requirements for trigger/DAQ documented and Rev 0 approved prior to our annual review this fall"
• Follow-up on discussion of input impedance to match beamline signals
• General discussion

Need two things by end of August (no hard deadline). Some of this is just cut/paste from existing docs.

1. Design requirements document -- examples and template : http://userweb.jlab.org/~rom/mollerdaq/design

2. ICD -- interface control document(s). -- apparently Robin Wines made a template and it's on sharepoint. It seems we need several of these (infrastructure to DAQ; detectors to DAQ, etc).

Resources

Response from Tom Powers about beamline sample and hold card output

Here is a schematic of one of the channels, which is in the EECAD directory as well as document control.

The LM6321 is a 50 Ohm driver with a gain of 1. The topology of having the 50 Ohm resistor where it is makes it such that the circuit can put out as much as +/-10 V to a high impedance load and +/-5 V to a 50 Ohm load. The topology is also such that the output voltage remains the same if you have a high impedance load or a 50 Ohm load and so long as you do not exceed +/-5 V.

The target value for the SEE wire signals is about 3.5 V or minus 3.5 V depending on which output channel you use. Thus it is a don't care on the load type.

My advice is that you can use high impedance for a local data acquisition system but it is recommended that you use a 50 Ohm termination if you are running long cables. Just remember that you only get one 50 Ohm load per signal.

Minutes

Recording on Bluejeans.com:

Participants: