Wireless Charging
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User Guide
Rev 2.0
TSDMRX-5W-EVM
Jun 2016
Semtech
Measure Efficiency
By measuring the power from the receiver’s VOUT+ and VOUT- pins in comparison to the power entering
the transmitter EVM, you can determine the efficiency of the power transfer through the system. For the
EVMs used here, the diagram below demonstrates that efficiency is a function of output current, and runs
about 75% at higher power levels, assuring good efficiency and minimal heat dissipation concerns.
Load vs Efficiency
Output Current (A)
E
ff
ic
ie
n
cy
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1