GSWP050W-EVBPA
GaN E-HEMT Wireless Power Transfer Evaluation Board
User’s Guide
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GSWP050W-EVBPA Rev 190304
© 2019 GaN Systems Inc.
www.gansystems.com 15
Please refer to the Evaluation Board/Kit Important Notice on page 22
•
DC power supply 50V/5A
•
TEK scope with current probe TCM0030A
•
Fluke 87 multimeter for input current
•
50dB 100W attenuator as load
•
Spectrum analyzer: RIGOL DSA 815
•
Power meter: GiGa 8542C
•
Thermal meter, sensor is located at screw of copper coin
Note: The WPT test setup is normally a non-
50Ω system.
If the PA is tested under a non-50
Ω
system, the
measurement results may not correlate with 5
0Ω
system due to the mismatch.
Hardware Operation
The following steps provide a guideline for proper hardware operation and configuration.
1)
First, set the current limit to 0.3A for the +5V
DC
supply feeding JP35.
2)
Set the current limit to 1A for the HV DC supply feeding J32 at a voltage of b10V
DC
and +10V
DC
.
3)
Verify that all DC power supplies are turned off.
4)
Make sure the load is connected to JP57.
5)
Verify the Class EF2 waveform via test points TP8, TP81 with JP35 +5V
DC.
6)
Connect the V
DD
power supply to J32. Apply between 4V to +10V
DC
to J32. Read the output power
at JP57.
7)
Turn on the HV supply to the desired value. Do not exceed the absolute maximum voltage of
+25V
DC
. Keep the JP35 +5V
DC
on.
8)
To power the evaluation board down, reverse the steps above.
Measurement Technique
When measuring the high frequency content switch node, care must be taken to avoid long ground
leads. Measure the switch node by placing the oscilloscope probe tip at TP192 and TP193 (designed for
this purpose) or to the closest ground screws. Refer to Figure 16
for the proper probe technique.