P9221-R Datasheet

© 2017 Integrated Device Technology, Inc.

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April 4, 2017

10.3 Identification and Configuration Phase

The identification and configuration phase is the part of the protocol that the power transmitter executes in order to identify the power receiver

and establish a default power transfer contract. This protocol extends the digital ping in order to enable the power receiver to communicate the

relevant information.

In this phase, the power receiver identifies itself and provides information for a default power transfer contract:



It sends the configuration packet.



If the power transmitter does not acknowledge the request (does not transmit FSK modulation), the power receiver will assume 5W output

power.

10.4 Negotiation Phase

In the negotiation phase, the power receiver negotiates changes to the default power transfer contract. In addition, the power receiver verifies

that the power transmitter has not detected a foreign object.

10.5 Calibration Phase

In the calibration phase, the power receiver provides information that the power transmitter can use to improve its ability to detect foreign objects

during power transfer.

10.6 Power Transfer Phase

In this phase, the P9221-R controls the power transfer by means of the following control data packets:



Control Error Packets



Received Power Packet (RPP, FOD related)



End Power Transfer (EPT) Packet

Once the “identification and configuration” phase is completed, the transmitter initiates the power transfer mode. The P9221-R control circuit

measures the rectifier voltage and sends error packets to the transmitter to adjust the rectifier voltage to the level required to maximize the

efficiency of the linear regulator and to send to the transmitter the actual received power packet for foreign object detection (FOD) to guarantee

safe, efficient power transfer.

In the event of an EPT issued by the application, the P9221-R turns off the LDO and continuously sends EPT packets until the transmitter

removes the power and the rectified voltage on the receiver side drops below the UVLO threshold.