ppk2 ampere meter measure error.not correct

[3Rsteven]

hi nordic,

when ppk2 entry Ampere meter.
the measure current not correct.(it seem the scale and offset error ,but can be enable/disable output)

(test circuit only vdd(3.3 extern power)->resistor5.1k->ppk2(in)-->ppk2(out)-->gnd(ppk2 gnd)
it should be 0.6mA,but the ppk2 only 60uA.? and other case it get error value(nrf52840 dk blinkly example  same issue*1)

when ppk2 entry soure meter.it be work
it is right value.
(it test use nrf52840 dk ,blinkly example)
https://i.imgur.com/pMqRzEY.png

measure example(error):
https://i.imgur.com/o41SGHp.png

app version:
https://i.imgur.com/TlxZCIo.png

ppk2 F.W version:
15:37:32.160 Validating firmware for device with s/n D55B03750145
15:37:32.177 Opening device with s/n D55B03750145

os:
# nRFConnect System Report - 2020-12-30T10-21-15.621Z

- System:     xxxx
- BIOS:       xxxx
- CPU:        1 x Intel Core i5-8265U 1.60 GHz 8 cores (4 physical)
- Memory:     1.2 GB free of 7.9 GB total
- Filesystem: C: (NTFS) 120 GB 94.9% used

- OS:         Microsoft Windows 10 Pro (10.0.19041) win32 ia32

- Versions
    - kernel: 10.0.19041
    - git: 2.21.0.windows.1
    - node: 12.13.0
    - python: 2.7.13
    - python3:

*1:

https://infocenter.nordicsemi.com/index.jsp?topic=%2Fug_ppk2%2FUG%2Fppk%2Fmeasure_current_ampere_meter.html

---

2020-12-30T02:18:09.168Z INFO Deselecting device
2020-12-30T02:18:27.807Z INFO Validating firmware for device with s/n D55B03750145
2020-12-30T02:18:27.814Z INFO Opening device with s/n D55B03750145
2020-12-30T02:18:28.606Z INFO PPK started
2020-12-30T02:18:28.624Z INFO PPK opened
2020-12-30T02:18:36.925Z INFO DUT ON
2020-12-30T02:18:40.149Z INFO Sampling started
2020-12-30T02:18:51.021Z INFO Sampling stopped
2020-12-30T02:18:59.541Z INFO DUT OFF
2020-12-30T02:19:54.636Z INFO Deselecting device
2020-12-30T02:19:54.698Z INFO PPK closed
2020-12-30T02:19:58.355Z INFO Validating firmware for device with s/n D55B03750145
2020-12-30T02:19:58.362Z INFO Opening device with s/n D55B03750145
2020-12-30T02:19:58.729Z INFO PPK started
2020-12-30T02:19:58.748Z INFO PPK opened
2020-12-30T02:20:06.226Z INFO DUT ON
2020-12-30T02:20:07.538Z INFO Sampling started
2020-12-30T02:20:14.812Z INFO Sampling stopped
2020-12-30T02:20:15.640Z INFO DUT OFF

[Øyvind]

Due to Christmas holidays our technical support team is lower staffed, and the response time will be longer. Also, most of our R&D our out of office until January 4th. We apologize for any inconvenience this may cause.

---

Hello, 
The PPK team is currently out of office. Please expect an answer within next week. 

Kind regards,
Øyvind

[hmolesworth]

The original problem about not measuring in Ampere Mode is caused because the PPK2 has been incorrectly connected to the board you are testing:

Change (3.3 extern power)->resistor5.1k->ppk2(in)-->ppk2(out)-->gnd(ppk2 gnd)

To     (3.3 extern power)->ppk2(in)    ppk2(out)->resistor5.1k->gnd(ppk2 gnd)

The PPK2 takes the difference in measured voltages because the measurement loads the input and output with 120k+30k each.