Fod Test - Semtech TSDMTX-19V3-EVM User Manual

FOD Test

In a production device, FOD testing is an important feature, in that the transmission process is constantly
inspected for the introduction of extraneous materials in the target area that could absorb the transmitted energy
and become hot. When Foreign Objects are Detected ("FOD"), the TS80003 shuts down power transmission as a
safety precaution, and indicates the detected problem by blinking the red status LED.
This process is bypassed in the receiver EVM, however, in order to allow engineers to test different antennas and
make other hardware modifications without triggering the FOD protocols and complicating the testing process.
When such hardware changes are made, the parameters of the feedback measurements change, which the FOD
protocol would perceive as a foreign object in the field, and cause the system to shut down.
In order to test the FOD protocol, the experimenter can use any Qi products certified to WPC 1.2.2 or higher as a
receiver. A list of such products can be found at:
http://www.wirelesspowerconsortium.com/products/?brand_name=&product_name=&type_number=&product_
type=2&compliant_automotive=&sort=&direction=asc
Experiments can be run on foreign objects on receivers with and without FOD management enabled to observe
the differences. With FOD disabled, the metal object in the field will absorb some of the transmitted energy and
become warm. Using a FOD-enabled production device, power transmission will be aborted when any significant
interference in power transfer has been detected.
Once a FOD abort takes place, the transaction is terminated, as indicated by a blinking red LED. To restart power
transmission, the receiver must be removed from the target area and a new transaction must be initiated. If the
FOD is still present, the transaction will fail again, and continue to do so until the FOD is removed from the target
area.
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User Guide Rev 2.0 14 of27
May-18
TSDMTX-19V3-EVM Semtech