Wireless Charging
www.semtech.com
6 of 17
User Guide
Rev 1.03
TSDMRX-19V20W-EVM Semtech
Measure Efficiency
By measuring the power from the receiver’s VOUT+ and - 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(TSDMRX-19V20W-EVM on TSDMTX-19V2-EVM), the diagram below demonstrates that efficiency is a function
of output current, and runs about 85% at higher power levels, assuring good efficiency and minimal heat
dissipation concerns.