January StudentZone Quiz Solution

Question:

Can you apply current division to obtain I1 and I2 for the circuit shown below? Explain briefly.

Try with various resistors 470 Ω, 1 KΩ, 4.7 KΩ. and 1.5 KΩ

When performing the Lab activity - how to connect the ADALM1000? 

 

Feel free to post your approach here so we could discuss.

 

For your reference see the Analog Dialogue Student Zone articles explaining the Source Measurement Unit (SMU) ADALM1000.

What is a Source Measurement Unit or SMU?

Parents
  • What about an answer to the first question ("How well did the measured outputs and calculated outputs compare? Explain any differences"). I found the measured values to be lower than the calculated values but don't have an explanation.
    When performing the same measurements with two multimeters, I found that the measured values are almost the same as the calculated values, so the explanation should be somewhere in the difference between a SMU and multimeter?

    (although this StudentZone is from beginning 2018, I still find it intereseting, hope you can answer!)

Reply
  • What about an answer to the first question ("How well did the measured outputs and calculated outputs compare? Explain any differences"). I found the measured values to be lower than the calculated values but don't have an explanation.
    When performing the same measurements with two multimeters, I found that the measured values are almost the same as the calculated values, so the explanation should be somewhere in the difference between a SMU and multimeter?

    (although this StudentZone is from beginning 2018, I still find it intereseting, hope you can answer!)

Children
    •  Analog Employees 
    on Mar 20, 2021 2:32 PM in reply to MartijnSc

    Has your M1k been calibrated? If you are using the Revision C version (6 pin analog I/O connector) it is probably not since these boards were not calibrated in the factory. If you have a newer board with the 8 pin analog I/O connector, Revision F, then it was factory calibrated and should be accurate to about  1mV.

  • Great to see you answer, gives me confidence to proceed with the other (older than 2000) trainings!

    I rebuild the circuit and it seems ok now. I have a Rev F version, and I may have goofed up with the Bin and Ch B pins. I just recently found out that for Meter Source you should use the Ch X pin, not sure what I used when first testing.

    •  Analog Employees 
    on Mar 21, 2021 12:29 AM in reply to MartijnSc

    The newest version of the Meter-Source tool (for use with Rev F) has an option for using the Split I/O inputs AIN and BIN. These Inputs have 100 ohm series resistors which might explain why you are seeing difference between CH A/B pins vs A/BIN pins when not in Split I/O mode.

  • I'm finding much information about the config, it does seem to be scattered a bit. I've made a diagram of the Rev F version, as found on the outer shell:

    S1 in this diagram would be the Split I/O function, right? The CH output would in all cases be the output of the Source. S2 would control wheter the SMU is in SVMI or SIMV mode.

    Then I found this diagram to be relevant:

    where I think the "Pin With White Circle", referring to Rev D PCB would be equivalent to the CH IN pin on the Rev F PCB.
    I think S1 in this diagram would relate to the Hi-Z setting in the AWG CH mode settings. S4 in this diagram would also have to be closed (but I guess that is standard operational mode) for a signal on CH A/B to be measured.

    Then I recon S2 and S3 control the AWG CH term mode, Open would mean S2 and S3 would be open, To GND would mean S3 is closed and To 2.5V would mean S2 is closed.

    Then S4 remains, probably that would be the Split I/O function, right? And although it is possible to have both Hi-Z and Split I/O selected in the AWG CH mode, i don't think that that would make a lot of sense, as both S1 and S4 in the second diagram would be open.

    By your last reply, do you mean that there is also a 100 Ohm resistor in series with the CH IN pin on the Rev F PCB?

    (your support effort is highly appreciated, especially considering it is weekend)

    •  Analog Employees 
    on Mar 21, 2021 4:19 PM in reply to MartijnSc

    Please refer to the Revision F schematic for complete specific details on the hardware:

    https://wiki.analog.com/_media/university/tools/m1k/02-037760-01-f.pdf