P9222-R/RN Datasheet

© 2019-2022 Renesas Electronics Corporation

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May 5, 2022

9.4.2 Modulation Capacitor and Interrupt Enables

The P9222-R/RN sends the communication packets to the transmitter using ASK modulation of the coil voltage. For ASK modulation, the

P9222-R/RN switches on and off the capacitors on the COM1, COM2, CMA, and CMB pins using internal MOSFETs. By default, the P9222-

R/RN switches only MOSFETs on the COM1 and COM2 pins. ASK modulation depth can be increased by enabling the switches on the CMA

and CMB pins. Measure the modulation depth on the transmitter demodulation circuitry, and if too small, adjust the ASK modulation depth by

enabling the CMA and CMB switches. Modulation depth can also be increased by increasing the capacitor value. The AP can also change the

ASK modulation depth by writing to the ASK modulation depth Registers (0xF4).

Using the /INT pin, the P9222-R/RN can interrupt the AP when there is a fault condition such as overcurrent or when there is a major state

change such as when the VRECT is turned on. The AP can enable or disable the interrupt conditions by writing to the Interrupt Enable Registers,

INT_Enable_L (0x38) and INT_Enable_H (0x39).

The default values of the ASK modulation depth and the interrupt enable registers can also be configured by writing a configuration file into the

external EEPROM.

To generate the configuration file using the P9222-R/RN Windows GUI:

1. Place the receiver with the P9222-R/RN onto the WPC transmitter or apply 5V from an external power supply on the VRECT node.

2. Launch the P9222-R/RN GUI, go to the “Config” tab, click the “Rd EEPROM” button, and then click the “MODcap,INT,ID” button. A new

popup window with the current values stored in the external EEPROM will be displayed.

3. Enter new values and click on the “Save cfg file” to generate a new configuration.

The configuration can also be directly written to the external EEPROM by clicking the “Wr EEPROM” button. Note: The Write Protect

function on the EEPROM must be disabled before writing to the EEPROM.

Figure 35. Modulation and INT Settings Tab