EVK-F9P-01 - User guide
UBX-22038408 - R03
Measuring current
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C1- Public
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Measuring current
At start-up, the receiver starts in acquisition state to search for available satellites and to download
GNSS orbital data, i.e., ephemeris and almanac. Once the data has been downloaded, the receiver
enters the tracking state. In continuous operation, the receiver typically remains in the tracking state
once entering it. The current consumption reduces when the receiver enters the tracking state. The
time required to enter the tracking mode can be reduced by downloading aiding data from the
AssistNow™ Online service.
To measure the total GNSS supply current with EVK-F9P, follow these steps:
1.
Place the EVK in clear sky view and perform the test with good signals to ensure that the receiver
can acquire the satellite signals.
2.
Power up EVK-F9P.
3.
Connect a true RMS voltmeter across CUR GPS1 (pin 12) and CUR GPS2 (pin 11) of the 14-pin
connector.
4.
Read the voltage (and average if necessary) on the voltmeter and convert to current (1 mV equals
1 mA).
☞
The total GNSS current includes the internal LNA, SPI flash and TCXO.
For more details see the schematic in
Figure 4: Example – tracking current measurement
Hirschmann
Part No.: 934160100
P1A (VCC)
P1B
P1B
P1A (VCC)
