Nineteen rails have a TI INA226 PMBus power monitor circuit with connections to the rail series current sense resistor. This arrangement permits the INA226 to report the sensed parameters separately on the PMBus. The rails equipped with the INA226 power monitors are shown in the power system table in Board Power System. As described in PMC MIO[46:47] I2C0 Bus, the I2C0 bus provides access to the PMBus power controllers and the INA226 power monitors via the U33 TCA9548A bus switch. All PMBus controlled Infineon regulators are tied to the PMBUS_SDA/SCL PMBus, while the INA226 power monitors are split across PMBUS1_INA226_SDA/SCL and PMBUS2_INA226_SDA/SCL.
The I2C0 bus topology figure and I2C0 port expander TCA6416A U233 address
0x20 connections table in PMC MIO[46:47] I2C0 Bus document the I2C0 bus access path to the Infineon PMBus
controllers and INA226 power monitor op amps. Refer to schematic for connectivity
details. This can be accessed through the VPK120 Evaluation Board website. These power system
components are also accessible to the ZU4 U125 system controller (bank 501) and the ACAP
U1 (bank 501).