Download Solved Lab - Electronic Circuits Laboratory | EE 371 and more Lab Reports Microelectronic Circuits in PDF only on Docsity! University of Portland School of Engineering EE371 Electronics Laboratory LAB HINTS PURPOSE: Construction and debugging of analog circuits demands a certain amount of finesse in the lab. The purpose of this Lab Hints Handout is to alert you to some “easy-to-do-hints” and some good lab habits and practices that you can do in the lab and with your lab kit to avoid the “pitfalls” of analog circuit layout, test and debug. HINTS: 1) Do not attempt to build a circuit in your lab kit until you have a good understanding of what you are doing theoretically. It is much easier to debug a circuit which you thoroughly understand. 2) When building your circuit in your lab kit, think small and Manhattan ! Keep your wiring flat with no loops. A neat, compact and Manhattan-style layout in your lab kit is less prone to parasitic effects and is much easier to debug. Keep your lead lengths as small as possible to avoid “antenna-effects”. 3) Always perform DC analysis, measurement and debug FIRST before moving on to AC analysis and measurements. Note that your entire circuit layout and DC analysis and testing can be done at home away from the lab. This will allow you to focus your valuable lab time on the more complex AC measurements. 4) Never make DC or AC current measurements nor AC voltage measurements using your DMM. Instead: 1) Use your oscilloscope to measure AC voltages, 2) Use your oscilloscope to measure AC currents by measuring the AC voltage across a known series resistor and then use Ohm’s Law, 3) Use your DMM to measure DC currents by measuring the DC voltage across a known series resistor and then use Ohm’s Law. 5) In order to make differential measurements between internal nodes in your circuit with your oscilloscope, you need to make two separate, dual-trace single-ended measurements with respect to Ground and then subtract the two measurements using the scope’s Math function. 6) To avoid high frequency oscillations, do not locate your output node near your input node on your circuit layout. Keep your output and input nodes as far apart as possible. 7) Avoid “draping” scope probes and DMM probes across your layout in a “willy-nilly” fashion. This can cause unwanted noise due to inductive pick-up and feedback between internal nodes and between the output and input nodes. 8) Use 10X scope probes only. Avoid 1X scope probes. 10X scope probes are much better since they load your circuit with a hefty 10MΩ and a negligible 6.7pF. Whereas, 1X scope probes will load your circuit adversely with a “wimpy” 1MΩ and a large 67pF.
