This document is the second part of "Multisim/Ultiboard Case Study Tutorial: Design and Implementation of myDAQ Compatible PCB".
It is important to make sure that your schematic capture produces the intended design behavior. To do so, you can refer to “Using myDAQ with NI Multisim Circuit Design Software” for more details on how to simulate a schematic design and compare it to a prototype using the NI ELVIS Soft Front Panels and instrumentation. This document will showcase the Adaptive Bandpass Filter example.
If you have the myDAQ myFilter PCB board and would like to replicate this simulation, you can find the Multisim/Ultiboard Files in "miniSystems: myDAQ myFilter Multisim/Ultiboard Files".
2. Simulating the Schematic Capture with myDAQ Instruments
The current design acts as an adaptive band-pass filter between 100 Hz and 1000 Hz. As instructed in the “Using BODE with FGEN” section, double-click the BODE instrument and make sure that the FGEN instrument is enabled. The band pass is shown in the following figure, the simulated data should appear in green, and you can stop the simulation.
Figure 5: BODE Analyzer plot of the schematic capture simulation
It is highly important to build a prototype of your schematic capture and to compare its behavior to the schematic capture. You can either prototype it on a breadboard or build a test PCB to account for reall world issues like current draw, impedance matching, and noise. Some of these issues may impact your circuit in a way the simulation cannot anticipate.
3. Prototype and Diagnostics with myDAQ Instruments
For our purposes, we built a breadboard prototype and connected it to the screw terminal of the myDAQ as shown in the following figure.
Figure 6: BODE Analyzer plot of the schematic capture simulation
As pointed out in the “Using myDAQ with NI Multisim Circuit Design Software” devzone article, under “Real Data: Data Acquisition using DAQmx Instruments” section, select your myDAQ device under Instrument Control in the BODE instrument.
Figure 7: Selecting myDAQ to Get Real Data
The op-Amp signal polarity is chosen to be inverted according to the design. The Run button is pushed, and the function generator will sweep through different frequencies to generate a yellow plot that represents the bode plot of the real data vs. the green plot of the simulated data.
Figure 8: BODE Analyzer plot of simulation data vs real data
4. Additional Resources
» Multisim/Ultiboard Case Study Tutorial: Design and Implementation of myDAQ Compatible PCB
» Using myDAQ with NI LabVIEW Graphical Programming Software
» Using myDAQ with NI Multisim Circuit Design Software
» View all myDAQ Set-up and Support Documents
» Visit the myDAQ Community and connect with myDAQ users
» miniSystems: myDAQ myFilter Multisim/Ultiboard Files
» miniSystems: myDAQ Advanced Template for Multisim/Ultiboard
» miniSystems: myDAQ Beginner Template for Multisim/Ultiboard
» NI Ultiboard Prototyping: Sunstone Circuits Prototyping Check List