Intrinsyc Open-X 8M, User Manual

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Open-X™ 8M Development Kit based on the NXP i.MX8™ Processor User Guide Version 1.0
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Copyright Intrinsyc Technologies Corporation
Power Probe Header J600
Figure 3-8 Power Probe Header J600
The power probe header is used to sense/ monitor the current on the 3.38V power rail going into the
SOM. The table below summarizes the pinout of header J600.
Table 3.8.4-1 Power Header Pin-out, J600
Description Signal Pin
SOM power positive
current sense line SOM_PWR_SENSE_P J600[1]
SOM power negative
current sense line SOM_PWR_SENSE_N J600[2]
GND GND J600[3]
To obtain power consumption measurements, the Power Probe Header J600 can be connected to a data
acquisition unit (such as a Keithley 2701) and the voltages on the SOM_PWR_SENSE_P/N pins should
be captured every few seconds over a test period (typically 30 minutes). The SOM power consumption
can then be calculated using the following formula (where Rsense = 5 milliohms):
𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃 = 𝑉𝑉𝑃𝑃𝑃𝑃𝑃𝑃
𝑆𝑆𝑆𝑆𝑆𝑆 _ 𝑃𝑃𝑃𝑃𝑃𝑃 _ 𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆 _ 𝑆𝑆
∗ �
�𝑉𝑉𝑃𝑃𝑃𝑃𝑃𝑃
𝑆𝑆𝑆𝑆𝑆𝑆 _ 𝑃𝑃𝑃𝑃𝑃𝑃 _ 𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆 _ 𝑃𝑃
− 𝑉𝑉𝑃𝑃𝑃𝑃𝑃𝑃
𝑆𝑆𝑆𝑆𝑆𝑆 _ 𝑃𝑃𝑃𝑃𝑃𝑃 _ 𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆 _ 𝑆𝑆
�
𝑅𝑅𝑃𝑃𝑅𝑅𝑅𝑅𝑃𝑃𝑅𝑅
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