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TPS40428: Current readout (READ_IOUT) does not seem to be correct.

Part Number: TPS40428

Tool/software:

Hello,

We are using a TPS40428 in multiphase output with a pair of CSD95378B devices to drive an FPGA core voltage at 0.75 Volts, pretty much per the schematic in the datasheet.

I am testing the PMBUS READ_IOUT command, and I am getting a value of 1 A (read value was 0xE010).  I am expecting it to be closer to 10 Amps.  1 AMP is too low.

I believe the PMBUS transactions are OK, as when I read the output voltage, I get 0.748047 volts and I am able to properly read the VOUT_COMMAND register, etc.

I have checked that the IOUT_CAL_GAIN register is set to 0.5 mOhm (0x8021).

Is there something I should be checking on the schematic?

Thanks,

Mike