P9221-R 15W Qi Wireless Power Receiver Solution by IDT

The video provides an overview of the P9221-R; a highly-integrated, Qi-compliant wireless power receiver targeted for 15W applications. Using magnetic inductive charging technology, the receiver converts an AC power signal from a resonant tank into a regulated 9V or 12V DC output voltage.

The video also demonstrates the P9221-R-EVK reference solution board, describing some of its features and offering some usage tips.

Presented by Julius Sarkis, application engineer at IDT. For more information about the P9221-R, visit www.IDT.com/P9221-R. For more information about IDT's turnkey wireless power reference kits, visit www.IDT.com/go/WPkits.


Hi, my name is Julius Sarkis, Wireless Power Product Marketing Manager at IDT. Today, I'll be talking about the P9221 evaluation board, which is part of our mass-market 15 Watt kit. The 15 W mass-market kit is comprised of a transmitter P9242, and a receiver P9221. The kit is WPC 1.2.2 certified. It is easy to use for reference designs and rapid prototyping. For this video, I will be focusing on the P9221 receiver.
Here are some of the features associated with the P9221. The receiver is designed to deliver up to 15 Watts of power. The DC-to-DC system peak efficiency is 87% at 15 Watts. The DC-to-DC is the efficiency from the transmitter using IDT's P9242-R up to the applied load to the P9221 receiver. 
The conditions for the efficiency testings are 12 volt applied to the transmitter. P9221 the receiver is set to 12-volt output voltage with 3-millimeter spacing. The maximum output current that the P9221 can deliver is 1.25 amp. The output voltage can be set to either 9 volts or 12 volts by connecting the center top of the resistor divider to the VO set pin. The default output voltage is set to 12 volts. The output voltage can automatically switch from 12 to 5 volts, supporting transmitters with only 5 W capability. There are three key features on the P9221. One is the embedded 32-bit ARM M0 processor, providing flexibility and programmability while reducing the power in the standby and sleep modes. The second important feature is the patented over-voltage protection clamp, which eliminates the external capacitors for lower PCB space, BOM, and cost. Lastly, the proprietary coil alignment guide is used for optimum coupling between the transmitter and the receiver for high efficiency and user experience.
The programmable current limit allows the system designers to adjust the current limit for their specific system requirement. The product includes an open-drain interrupt flag signal. It asserts high when the over-voltage, over-temperature, and over-current fault conditions are triggered. The receiver supports I2C serial interface to read back information such as output voltage, output current, and resonance frequency. Lastly, the P9221 is available in a 52-pin chip scale package with total area of 10.5 mm2. 
The P9221 wireless power receiver board is a four-layer board. It has two ounces of copper on the top and the bottom of the layers while one ounce of copper is on the internal layers. The board thickness is 0.66 millimeters. Smallest capacitor size is 0201, while the smallest resistor is 0402. The total active area as shown by these two score lines is 420 mm2. The black area shown right over here is the receiver's coil, which is connected to the internal synchronous rectifier. Flipping the board over is the PCB coil used for IDT's patented alignment guide information. In the center of the board is the P9221 controller. When testing the board, the black area must be facing up. We have used the PCB thickness as the spacer or the gap between the transmitter and the receiver. 
There are two important test points on the board. One is the rectifier voltage, which is the voltage from internal synchronous rectifier, and the other important test point is the regulated output voltage shown over here with the two test points. When testing the board, be sure to attach the load at the output of the P9221 controller and not at the rectifier test points. Once the P9221 evaluation board is placed on top of the transmitter, as shown over here with the P9242, and the connection is established, a green LED will illuminate indicating a connection has been established and the board is ready for power delivery.
This concludes the P9221 wireless power receiver module. For more information, please visit IDT's website. I'm Julius Sarkis and thank you for listening.