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UCD9090A: A Rail IOut Cal Gain doesn't read back the same value as written.

JEB
Prodigy 230 points
Part Number: UCD9090A

Using both Fusion version 7.1.1 and 7.2.1 when a rail's IOut Cal Gain is configured with a value of 1500 mOhms and the XML project is imported to the device after completion Fusion shows a value of 1538 mOhms.  And using the Fusion comparison tool to compare the project to the device that parameter is flagged as not matching.

I can see from the log that a value of 0x0AEE is written to register 0x38 during the import: 

    "Wrote IOUT_CAL_GAIN [0x38,Rail #5] 1,500.000000 m? [0x0AEE] to RAM". 

It appears that register is formatted with "Linear Data Format" so a value of 0x0AEE contains a mantissa of 0x2EE (750) and an exponent of 1 which represents a real world value of 750*2^1 = 1500.  So, why is it that when it is read back after the import the value is 1538 mOhms?

Thanks