3 The Power Profiler Kit overview
Doc. ID 4425_027 v1.0
Page 9
• DK interface
• PPK on-board voltage regulator
• External supply
The power supply is selected by the power select switch (SW4).
The PPK on-board voltage regulator is supplied by the 5 V USB power supply. Its output can be adjusted
between 1.8 V and 3.6 V by the nRF52832 through the PPK desktop application.
If an external power supply is used, the voltage is applied directly to the circuits without regulation. This
voltage must be limited to the 1.8 - 3.6 V range.
When the DK is selected as the power supply, the DK supplies the PPK circuitry.
The analog part of the automatic switch circuitry requires a 5 V power supply. When the PPK is connected to
an nRF5x DK, the 5 V is supplied by the DK. When the PPK is used standalone, a USB cable has to be connected
to supply the 5 V required by the circuitry.
Measurement ranges and switching points
In order to have high measurement dynamic range, the PPK features three calibrated parallel measurement
means realizing the three measurement ranges simultaneously. An automatic range switching mechanism
always selects the correct measurement range depending on the instantaneous current draws by the DUT.
If your DUT has a current consumption that is close to a switching point, it will cause rapid switching up and
down between the ranges and create measurement errors and distorted plots. A hysteresis is applied at the
switching point in order to avoid distorted measurements as shown in
Figure 5: Measurement ranges and
on page 9.
There are four switching points:
•
Switch up LO
: Switches up from low to medium range
•
Switch up HI
: Switches up from medium to high range
•
Switch down HI
: Switches down from high to medium range
•
Switch down LO
: Switches down from medium to low range
Figure 5: Measurement ranges and switching points
DUT output
The PPK supports two modes of operation:
• Current measurements on the nRF5x DK device
• Power supply and current measurements on an external board
