The XRF4 System Controller uses two different I2C interfaces: PS_I2C and
PL_I2C. The PS_I2C interface controller is integrated into the XRF4 SOM PS. The
PL_I2C interface controller is located inside the SOM FPGA logic and controlled as
an AXI interface of the SOM PS. The PS_I2C interface is used to control the power
supply unit (PSU) for RF slices and measure the voltage/current of the three slice
power rails (VDD, 3.3 V, 5.0 V). At any given time, only one PSU can
communicate with the PS_I2C. Two I2C MUX devices (0x76 and 0x77) are combined to select
the required slice PSU. The PL_I2C interface can be used to read the slice EEPROM
and temperature sensor located on the TX slice. The following table describes the
I2C interface devices.
| Interface Name | Device Location | Target/Device Name | Peripheral Device Address | Description |
|---|---|---|---|---|
| PS_I2C | Slice | TCA9548 MUX select[MR1] |
0x76, 0x77
|
8-channel I2C switch is used for selecting I2C devices. Seven
devices are connected to the |
| Slice/RFBB | INA3221 PSU monitor |
0x40
|
Each slice has a INA3221 PSU monitor and RFBB has one device for monitoring the SOM voltage/current. | |
| Slice | TCA9535 I/O expander |
0x20
|
The 16-bit I/O expander has two ports. Each port with eight I/O Read/Write bits is connected is power supply unit of the slice. | |
| RFBB | CAT24C256 EEPROM |
0x51
|
RFBB has an EEPROM device with 32 KB capacity and a page size of 32 bytes. | |
| RFBB | TPS55288 DC-DC converter |
0x74
|
DC-DC buck-boost converter with adjustable output. | |
| PL_I2C | Slice | CAT24C256 EEPROM |
0x54
|
Slice has an EEPROM with 32 KB capacity and a page size of 64 bytes. This EEPROM is used for storing slice configuration and performance specifications. |
| Slice | TMP116NAIDRVT temperature sensor |
0x48
|
TX slice temperature sensor. |