the result of PPK2 is too different with it of keysight 6705C

[andy]

I measure the same board with PPK2 and 6705C,  but they show different result of the measurement.  

The power supplied by PPK2 and 6705C with 3.6V.

PPK2's average current is about 4-5mA, but 6705C's average is about 1.4mA.

i have tested the PPK2 with the resistance 100R/3V and 1M/3V ,  it measured correctly.

I thought PPK2 is too weak at measuring  quick changing current,  is that correct?

and i compare two different PPK2 s with 6705C serval times,  the PPK2 shows the same big difference to 6705C.  

There are two pic below,  it is the details of the same board current measurement by PPK2 and 6705C.

[Priyanka]

Hi Andy,

I am looking into this but please expect a slight delay as I am a bit occupied with another case and we are short staffed at the moment due to the summer vacation.

In the meantime, could you describe your PPK2 setup? How did you connect it? Which version of PP kit is it?

Best Regards,

Priyanka 

[andy]

Thanks for your reply,

1\   I never change the advanced settings,  so it is the default value.   

      the basic setting are below, Source meter, supply voltage is 3000mv,   100,000 samples per second, sample for 300 seconds.

2\  I connect the GND and VOUT of the PPK to the DUT.

3\ My PPK is PPK2,  PCA63100 1.0.1 2022.30 C0E 3AC 4E 

    Version of Power Profiler is 3.5.5

[Priyanka]

Hi Andy,
Apologies for the delayed response. I am working on this and will get back to you soon. I have discussed this with the internal team and will update you as soon as I get a solid response.

Regards,

Priyanka

[Priyanka]

Hi Andy,

I would suggest you to try redoing the measurements with a more precise settings on the instrument. Because it looks like the measurement period of the 6705C readings is 20us, which means 50.000 samples/second AND the PPK2 is set to double that.

From the picture of the PPK, it seems like the waveforms look more clean and they do reach 0uA, while on the other instrument, it never reach 0A. Also, as you used 2 PPK2s and got the same result, you can either use a third instrument or increase the accuracy of the 6705C.

Regards,

Priyanka

[andy]

I did a comparison test using several different devices, there are keysight 6705C ,  EFM32 Happy gecko starter kit,  Fluke 15B digital multimeter. but only the ppk2 got the wrong measurement. 

So, i did another  simple test to  figure out  what the issue of ppk2 is, let me descript it below.

1\   Connect  VOUT_PPK2 and to the VOUT of PPK2.

2\   Generate a PWM plus from a MCU to switch on/off Q1,  

      and i measure the current throught the res R1 by PPK2(source meter mode)

3\  I change the period of the PWM ,   and got the wave of cureent  by PPK2  .

4\  I show the result of the wave below. i also upload the data files export from PPK2.

1Kohm_3v3_1ms.ppk1Kohm_3v3_1sec.ppk

[andy]

 Priyanka 

Could you reply it?  thanks a lot!

[Priyanka]

Hi Andy,

I had already replied to your query 21 days back. Please go through that and let me know in case you have further doubts.

-Priyanka