Wireless Charging
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User Guide
Rev 2.0
TSDMRX-5W-EVM
Jun 2016
Semtech
Standard Use
The TSDMRX-5W-EVM is very easy to use. Start by applying power to the TSDMTX-5V-EVM transmitter.
A few times each second, the transmitter emits a ‘ping’ of energy in search of a compliant receiver in
range - in this document, the TSDMRX-5W-EVM.
Place the TSDMRX-5W-EVM over the target area of the transmitter EVM. The TSDMRX-5W-EVM is
initially powered by the ping sufficiently to be able to announce its presence to the transmitter, and a
transaction begins. The transmitter next provides a small amount of power to the newly discovered
receiver, so the TSDMRX-5W-EVM can tell the transmitter what its power requirements are.
At the completion of the handshake, the transmitter begins providing the requested power, indicated by a
green LED on the receiver EVM. During power transfer, the TSDMRX-5W-EVM continuously
communicates with the transmitter, actively directing the process. In this way, it is assured that power is
only sent when and how it is required by the receiver. If required by the load, the TSDMRX-5W-EVM can
actively increase or decrease its power request, and the transmitter will act accordingly. As such,
equipment with complex charging requirements can be precisely supported by the TSDMRX-5W-EVM
and only the desired amount of power is provided. If at any time an error is detected, transmission is
halted. To restart, the TSDMRX-5W-EVM must be removed from the range of the transmitter and
returned to the target zone to start a new transaction.
The receiver EVM can deliver up to 5 watts of power at 5 volts to any load the user would like to
experiment with. For general experimentation, the optimal load to select would be a Programmable DC
Electronic Load. A ‘load box’ can easily be set to draw a selected current or power at the turn of a knob,
making them very flexible and easy to use in observing power supply operation in general. If a load box is
not available, a power resistor decade box is nearly as convenient, as it can easily be set to any desired
resistance to simulate a range of load conditions. In either case, be sure the test load is rated for at least
the amount of power being tested. If need be, a selection of power resistors could be used as test loads,
though without the ease of modification of the prior options. Finally, any device that uses a 5 volt input up
to 5 watts of power can be used as a test load should that be desired.
Status
LED